Hotplate & Stirrer

Magnetic Stirrers

<h2>What Are Laboratory Magnetic Stirrers?</h2>
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A laboratory magnetic stirrer uses a rotating permanent magnet or electromagnet installed below a flat work surface to create a spinning magnetic field above the plate. A PTFE (polytetrafluoroethylene)-coated magnetic stir bar placed inside a vessel couples to this field and rotates, mixing the liquid from within. Because there is no physical contact between the stirrer and the contents of the vessel, the technique is contamination-free, amenable to closed-vessel operation, and compatible with corrosive, biological, and hazardous reagents. Magnetic stirrers are used without heating for buffer and media preparation, titrations, pH measurement, enzyme inhibition assays, hybridization reactions, and dissolution studies. Multi-position magnetic stirrers drive multiple stir bars simultaneously on a single unit, enabling parallel sample processing in analytical laboratories, pharmaceutical quality control, and environmental testing workflows. Use a standalone magnetic stirrer (no heat) when you need uniform mixing without thermal input: titrations, pH measurement, cold-room work, and mixing heat-labile reagents.
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<h2 dir="ltr">What You Will Find:&nbsp;</h2>
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Digital hotplate magnetic stirrers offer precise temperature control up to 550&deg;C and dual LED displays, making it easy to monitor both heat and speed at a glance.
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High-capacity magnetic stirrers are designed to handle larger volumes with ease, providing the powerful torque needed for consistent mixing in bigger batches.
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Compact and ultra-flat stirrers provide a space-saving solution for crowded benchtops, featuring low-profile designs and PET surfaces that are tough and easy to clean.
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Multi-channel magnetic stirrers allow you to stir up to 10 samples simultaneously with uniform speed, perfect for boosting your lab&rsquo;s productivity.
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Analog and classic stirrers bring reliable, straightforward performance to your workstation with durable stainless steel or ceramic-coated plates that resist wear and tear.
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Auto-reverse and timer functions give you professional-level control over your mixing cycles, ensuring your samples get exactly the treatment they need.
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<h2>How to Choose a Magnetic Stirrer</h2>
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Single-position vs. multi-position
Single-position stirrers are the most common format for benchtop chemistry and biology work, accommodating one vessel at a time. Multi-position magnetic stirrers (2, 6, 10, or 15 positions on a single plate) are used for high-throughput applications such as dissolution testing, parallel reaction screening, and environmental sample preparation, where identical mixing conditions across multiple vessels are required simultaneously.
Digital vs. analog control
Analog (dial-control) magnetic stirrers are reliable, low-maintenance, and appropriate when mixing speed precision is not critical. Digital stirrers display speed in rpm, maintain the setpoint with a feedback motor controller, and provide reproducible speed settings session to session, which is important for protocols requiring a specific agitation rate (e.g., OD600 turbidity assays, viscosity studies). Some digital models log rpm and run-time data via USB.
Speed range and stir bar compatibility
Most magnetic stirrers cover 100 to 1500 rpm. Microplate and high-throughput models reach up to 1500 rpm with small stir bars. For large-volume vessels (3 L and above), a lower maximum speed (300 to 500 rpm) with a large stir bar (60 mm to 80 mm) is more appropriate than attempting high speed with an undersized bar. PTFE stir bars are available in lengths from 3 mm (for microcentrifuge tubes) to 80 mm (for large vessels); octagonal, cross-shaped, and egg-shaped bars improve mixing in round-bottom flasks compared to standard cylindrical bars.
Plate size and chemical resistance
Plate dimensions determine the largest vessel the stirrer can stably support. A 135 mm x 135 mm plate accommodates a 1 L beaker; larger plates (200 mm x 200 mm and above) are needed for 3 L to 5 L vessels. PTFE-coated plates or ceramic tops offer the highest chemical resistance for work with acids, bases, and organic solvents. Stainless steel tops provide stronger magnetic coupling for viscous materials.
Cold-room and CO2 incubator use
Magnetic stirrers designed for cold-room use (2 degrees C to 8 degrees C) or for operation inside a CO2 incubator use sealed, humidity-resistant motor housings and are rated for continuous operation under those environmental conditions. Standard benchtop stirrers are not rated for cold-room or high-humidity incubator use; using them in these environments shortens motor life.
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<h2>Specifications Context</h2>
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Motor type affects long-term reliability: brushless DC motors require no maintenance and last longer than brushed motors, which need periodic brush replacement in continuous-use settings. PTFE stir bars should be replaced when the PTFE coating chips or shows wear; bare metal exposure contaminates the solution and interferes with magnetic coupling. For regulated applications (pharmaceutical QC, ISO 17025 labs), specify a stirrer with a digital speed display and speed accuracy of plus or minus 1 rpm to support protocol documentation requirements. Related equipment:&nbsp;<a href="https://mbpinc.net/equipments/temperature-control-equipment/hotplate-and-stirrers"></a>
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Ready to find the perfect spin for your lab? Browse our magnetic stirrer collection and <a href="https://mbpinc.net/contact-us">reach out to the MBP team</a> for a quote today.

Analog Magnetic Stirrers (7.5 x 7.5″) Series

Benchmark Scientific H4000 series — 7.1 × 7.1 in chemical-resistant ceramic surface, 60–1,500 RPM. Six configurations: H4000-S/S-E (stirrer 115V/230V), H4000-HS/HS-E (hotplate + stirrer 115V/230V), H4000-H/H-E (hotplate 115V/230V).

Temp. Range

Speed Range

Platform Dimensions

Operating Temp. Range

Max. Stirring Capacity

Dimensions

Weight

Electrical

Warranty

Manufacture

Magnetic Stirrer, 7.5"x7.5", 115V

Hotplate Magnetic Stirrer, 7.5"x7.5", 115V

Hotplate Magnetic Stirrer, 7.5"x7.5", 230V

Hotplate, 7.5"x7.5", 115V

Hotplate, 7.5"x7.5", 230V

Magnetic Stirrer, 7.5"x7.5", 230V

Overhead Stirrers

<h2>What Are Overhead Stirrers?</h2>
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An overhead stirrer is a laboratory mixing instrument that mounts a motor unit above the sample vessel on a stand or clamp, driving a rotating shaft and impeller that is immersed directly into the liquid. Unlike magnetic stirrers, which rely on a rotating magnetic field to spin a small bar inside the vessel, overhead stirrers use direct mechanical drive: the motor connects to the impeller shaft through a chuck or collet, allowing the motor to deliver consistent torque to the sample regardless of viscosity changes during mixing. This makes overhead stirrers the correct choice for applications where a magnetic stir bar would stall or decouple: polymerization reactions, emulsion preparation, gel dispersion, cell suspension in bioreactors, slurry processing, and large-volume buffer and media preparation. Digital overhead stirrers with brushless DC motors, torque display, programmable speed ramps, reversible rotation, and overload protection are standard research-grade configurations covering volumes to 200 L. Switch from a magnetic stirrer to an overhead stirrer when the sample volume exceeds 2 L, viscosity exceeds roughly 2,000 mPas (similar to glycerol), or the stir bar stalls during the mixing process.
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<h2 dir="ltr">What You Will Find:</h2>
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<li>Digital overhead stirrers for laboratory mixing and sample preparation applications.</li>
<li>Stainless steel propellers available in one-line, four-arm, paddle with flat holes, and centrifugal impeller designs.</li>
<li>PTFE (Teflon) propellers offered in one-line, four-arm, paddle with flat holes, and centrifugal impeller configurations.</li>
<li>Optional interchangeable propellers allow optimization of mixing performance for different sample types and viscosities.</li>
<li><a href="https://mbpinc.net/equipments/temperature-control-equipment/hotplate-and-stirrers/overhead-stirrers/overhead-stirrer-accessories">Overhead stirrer accessories</a> support routine laboratory stirring, blending, and homogenization tasks.</li>
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<h2>How to Choose an Overhead Stirrer</h2>
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Torque capacity
Torque (measured in N &middot; cm) is the most important selection criterion for overhead stirrers. The motor must maintain its setpoint rpm against the resistance of the sample throughout the mixing process, including at points of highest viscosity (e.g., during emulsion formation or cooling of a polymer melt). Common torque classes are 20 Ncm, 40 Ncm, and 75 Ncm for lab-scale models. High-viscosity applications (pastes, gels above 10,000 mPas) require 40 Ncm or more. Models with a real-time torque display let the operator monitor process state during mixing; torque reaching a setpoint can signal batch completion.
Speed range
Low-speed overhead stirrers (12 to 300 rpm) are used for gentle laminar flow mixing and tangential agitation of high-viscosity materials to prevent air entrainment. Mid-range models (60 to 2,000 rpm) handle general stirring through turbulent flow. High-speed models (up to 6,000 rpm) are used for homogenization, emulsification, and dispersion at small to medium scales. Match the speed range to the flow regime required by the application.
Volume capacity
Overhead stirrers specify maximum volume based on water viscosity at the stated rpm. Actual volume limits for viscous samples are lower. Benchtop models cover 2 L to 15 L; mid-range floor-stand models reach 80 L; large-scale process-development stirrers handle up to 200 L. Confirm that the impeller diameter is appropriate for the vessel diameter in use.
Impeller type
Impeller geometry determines the mixing regime: propeller-type impellers generate axial flow for general liquid blending; paddle and anchor impellers provide tangential flow for high-viscosity materials; dispersing disc impellers create radial high-shear flow for emulsification and dispersion; and ribbon impellers handle very high-viscosity pastes and thickening batches. Impeller shafts and heads are commonly made from stainless steel or PTFE for chemical resistance.
Digital vs. analog control
Digital overhead stirrers display speed in rpm, maintain setpoint through closed-loop motor control, and include overload protection, reversible rotation, and data logging capability. Analog models use a dial for speed setting and provide no readout. For regulated or reproducible workflows, digital control is strongly recommended.
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<h2>Specifications Context</h2>
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Motor type affects long-term reliability: brushless DC (BLDC) motors require no brush replacement, operate quietly, and maintain consistent torque at low speed, which is important for laminar flow applications. Overload protection (automatic speed reduction or shutdown when torque exceeds a setpoint) protects both the motor and the sample from damage during unexpected viscosity increases. Shaft and impeller material should be confirmed for chemical compatibility: stainless steel (grades 304 or 316) suits aqueous and mild organic media; PTFE shafts are required for corrosive acids, bases, and halogenated solvents. Support stands should be rigid enough to prevent shaft wobble at speed; confirm the stand's load rating and reach for the vessel configuration in use.&nbsp;
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Ready to power through your toughest mixing projects? Take a look at our overhead stirrer range and <a href="https://mbpinc.net/contact-us">reach out to the MBP team</a> for a friendly quote today.

Product Literature

Optional propeller, stainless steel paddle with flat holes

Optional propeller, stainless steel centrifugal impeller

Optional propeller, stainless steel one line

Optional propeller, Teflon paddle with flat holes

Optional propeller, Teflon centrifugal impeller

Included propeller, stainless steel 4 arm

Benchmark Scientific Overhead Stirrers

The Benchmark Scientific Overhead Stirrer Series by Benchmark Scientific is the OS-20L digital overhead stirrer with a 20-litre mixing capacity, 30–2,200 rpm speed range, 40 Ncm maximum torque, and a DC brushless motor rated for up to 10,000 mPas viscosity. The tool-free 0.5–10 mm feed-through chuck, LCD display, universal 100–240V power input, and IP42 protection make the OS-20L a practical overhead stirrer for large-volume buffer preparation, viscous polymer blending, and bioreactor vessel agitation in research and pilot-scale labs. Available models: IPS2050-20, IPS2050-20-E, IPS2050-40, IPS2050-40-E.

Model

Mixing Capacity (H20)

Maximum Torque

Input Power

Output Power

Net Weight (Mixer)

Maximum Viscosity

Motor Type

Chuck Diameter Range

Exterior Dims.

Protection Mode

Ambient Operating Range

OS20L Overhead Stirrer, 20L includes stand, and 4 arm propeller (IPS2050-P-S4), 100 to 240V with US Plug

OS20L Overhead Stirrer, 20L includes stand, and 4 arm propeller (IPS2050-P-S4), 100 to 240V with EU Plug

OS40L Overhead Stirrer, 40L includes stand, and 4 arm propeller (IPS2050-P-S4), 100 to 240V with US Plug

OS40L Overhead Stirrer, 40L includes stand, and 4 arm propeller (IPS2050-P-S4), 100 to 240V with EU Plug

Biologix® FlatSpin Magnetic Stirrer 1 Piece/Case

BIOLOGIX FLATSPIN MAGNETIC STIRRER. MAGNETIC STIRRER FEATURES  A SPEED RANGE OF 15-1500 RPM. UNIT OPERATES ON 100V-240V/50HZ/60HZ. PRICE/EACH

Biologix FlatSpin 01-3201 magnetic stirrer, 90×90mm platform, 15–1,500 RPM, 0.8L capacity, 2.0kg max load, 0.3kg, 100–240V, auto rotation-reversing. ABS. 1 piece/case.

Hotplate & Stirrer Accessories

<h2>What Are Hotplate and Stirrer Accessories?</h2>
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Hotplate and stirrer accessories are supplementary components for single-position and multi-position hotplate stirrers that improve temperature accuracy, expand vessel compatibility, enable reflux setups, and maintain equipment in working condition. The most important accessory for research-grade hotplate use is an external temperature probe, which monitors actual solution temperature rather than hotplate surface temperature, which can be 20 to 50 degrees C higher than the liquid in the vessel. PTFE stir bars in standard cylindrical, oval, octagonal, cross-shaped, and polygon geometries allow matching of bar shape to vessel type and mixing requirement. Support rods and clamp assemblies secure condensers, separating funnels, and other glassware above the hotplate for reflux chemistry. Magnetic stir bar retrieval wands recover stir bars from flasks without contaminating the solution. An external temperature probe is the single most impactful hotplate stirrer accessory: without one, you are controlling plate temperature, not solution temperature, and the two can differ by 20 to 50 degrees C.
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<h2 dir="ltr">What You Will Find:</h2>
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<li data-section-id="dpsp0x" data-start="25" data-end="139">Temperature sensors for compatible GHS-series hotplate stirrers, available in standard and glass-coated designs.</li>
<li data-section-id="yvvor4" data-start="140" data-end="248">Sensor support stands and clamps for secure positioning of temperature probes during heating applications.</li>
<li data-section-id="hdqu1" data-start="249" data-end="353">Support rods and clamp sets for mounting laboratory apparatus and accessories above hotplate stirrers.</li>
<li data-section-id="rtdv85" data-start="354" data-end="446">Magnetic stir bars, including standard and pivot ring styles, for efficient sample mixing.</li>
<li data-section-id="1hl26tt" data-start="447" data-end="560" data-is-last-node="">Chemically resistant clamp set options featuring inert PTFE construction for demanding laboratory environments.</li>
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<h2>How to Choose Hotplate and Stirrer Accessories</h2>
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External temperature probes
Confirm probe type compatibility with the hotplate stirrer model: most digital hotplate stirrers accept either a PT1000 resistance temperature detector (RTD) or a Type K thermocouple, and these are not interchangeable between models. The probe is inserted directly into the solution and feeds temperature data back to the PID controller to maintain the solution (not the plate surface) at the setpoint. Probe length and sheath material (stainless steel, glass, or PTFE) should be matched to the vessel size and chemical compatibility requirements.
PTFE stir bars: geometry and size
PTFE stir bars are available in cylindrical, oval (egg-shaped), octagonal, cross (X-shape), polygon, and ring geometries. Cylindrical bars are the most common general-purpose format. Octagonal bars provide more turbulent mixing in flat-bottomed vessels than cylindrical bars. Cross-shaped bars improve mixing in round-bottom flasks by preventing the bar from riding the wall. Ring or hoop bars are used for mixing around fixed probes or frits inside the vessel. Stir bar length is selected to match vessel diameter, typically 30 to 50% of vessel inner diameter.
Support stands and clamp sets.
Support stands (rod-and-base assemblies) mount above or adjacent to the hotplate to hold condensers, addition funnels, thermometers, and other glassware in reflux setups. Confirm rod diameter compatibility with the clamp set (most lab glassware clamps fit 12.7 mm or 16 mm rods). Weighted bases provide stability for tall assemblies. Crossbar assemblies allow horizontal positioning of clamps at adjustable heights along the support rod.
Magnetic stir bar retrieval tools
Stir bar retrievers are magnetic wands encased in a non-contaminating sleeve (PTFE or glass) that attract and remove the stir bar from a vessel without inserting fingers or metal into the sample. Available as handheld wands or bench-mounted extractors. An essential accessory for labs processing multiple samples per day, as losing track of stir bars is among the most common minor equipment management issues in bench chemistry.
Replacement sensors and calibration weights
Temperature probes degrade after repeated heating cycles or chemical exposure; replace probes showing drift against a calibrated reference thermometer. For hotplate stirrer models with external calibration weights (balance verification), confirm the weight set is OIML or ASTM traceable for regulated workflows.
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<h2>Specifications Context</h2>
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PTFE stir bars should be inspected regularly for chipped or worn PTFE coating. Bare metal exposure from a chipped bar contaminates the sample with metallic particles and alters the bar's magnetic coupling properties, resulting in reduced mixing efficiency or bar stall at lower speeds. Discard and replace any stir bar showing PTFE damage. For regulated lab environments (GMP, ISO 17025), maintain a stir bar inventory log and retire bars on a scheduled basis. External temperature probes rated for immersion in aqueous solutions should be verified against a calibrated reference thermometer at least annually; probes showing more than 1 degree C deviation should be recalibrated or replaced.&nbsp;
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Looking for that one missing piece to complete your setup? Browse our accessories collection and <a href="https://mbpinc.net/contact-us">reach out to the MBP team</a> for a friendly quote today.

Clamp set for H3770 Chemically resistant/inert teflon, includes rod and clamp

The H3770-CSTF by Benchmark Scientific is an inert PTFE (Teflon) clamp set—including rod and clamp assembly—for Benchmark H3770 series digital hotplates and hotplate stirrers (H3770-H, H3770-S, H3770-HS). The chemically resistant PTFE construction suits corrosive acid, base, halogenated solvent, and high-purity chemistry workflows where standard metal clamp hardware would corrode or contaminate.

Clamp set for H3770, includes rod and clamp

H3770-CS by Benchmark Scientific is a clamp set — including a metal rod and universal clamp — designed to secure thermometers and temperature probes to the Benchmark H3770 Digital Hotplate/Stirrer. It keeps monitoring accessories at a fixed position during heating and stirring, ensuring reproducible readings. Ideal for chemistry and biology labs running temperature-controlled protocols with the H3770 platform.

<h2>What Are Laboratory Hotplates and Stirrers?</h2>
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Laboratory hotplates are electrically heated work surfaces used to warm flasks, beakers, and vessels containing reagents, culture media, buffers, and reaction mixtures. Magnetic stirrers use a rotating magnetic field beneath the plate to spin a PTFE-coated stir bar inside the vessel, providing uniform mixing without mechanical contact. Combination hotplate-stirrer units integrate both functions in a single instrument and are the most common format in chemistry, biology, and pharmaceutical labs. Standalone magnetic stirrers (without heating) are used for room-temperature mixing, pH measurement, and buffer preparation. Applications include chemical synthesis and recrystallization, cell culture media preparation, buffer and reagent preparation, dissolution testing, enzyme assays, protein and nucleic acid precipitation, and polymer synthesis. Digital hotplate-stirrers with PID temperature control, external probe inputs for actual solution temperature monitoring, and PTFE-coated ceramic or aluminum plates are the standard in research-grade instruments. Choose a combination hotplate-stirrer for most bench chemistry and biology work; choose a standalone magnetic stirrer for room-temperature mixing where a heating element would be a contamination or safety risk.
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<a href="https://mbpinc.net/equipments/temperature-control-equipment/hotplate-and-stirrers/magnetic-stirrers" title="Magnetic Stirrers">Magnetic Stirrers</a> provide powerful, quiet rotation using high-quality magnetic bars to ensure your liquids are blended perfectly every time.
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<a href="https://mbpinc.net/equipments/temperature-control-equipment/hotplate-and-stirrers/hotplate-and-stirrer-accessories" title="Hotplate &amp; Stirrer Accessories">Hotplate &amp; Stirrer Accessories</a> include everything from extra stir bars to external temperature probes, helping you customize your setup for better accuracy.
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<a href="https://mbpinc.net/equipments/temperature-control-equipment/hotplate-and-stirrers/multi-position-hotplate-stirrers" title="Multi-Position Hotplate Stirrers">Multi-Position Hotplate Stirrers</a> allow you to process several samples at once with uniform heat and speed, making your high-throughput days much more manageable.
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<a href="https://mbpinc.net/equipments/temperature-control-equipment/hotplate-and-stirrers/overhead-stirrers" title="Overhead Stirrers">Overhead Stirrers</a> deliver the high-torque power needed for thick, high-viscosity liquids that standard magnetic stirrers just can't handle.
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<h2>How to Choose a Lab Hotplate or Stirrer</h2>
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Hotplate-only vs. stirrer-only vs. combination unit
Hotplates without a stirring function are used for applications requiring only controlled heating: drying samples, warming baths, or maintaining solution temperature without agitation. Standalone stirrers (no heating) handle room-temperature mixing, titrations, and sample homogenization without thermal risk. Combination hotplate-stirrers serve both purposes in one instrument and are the standard choice for chemistry and cell biology benches where both heating and mixing are regularly needed.
Plate material: ceramic vs. stainless steel vs. aluminum
Ceramic top plates resist corrosive chemical spills, provide a white surface ideal for titrations and colorimetric work, and withstand temperatures up to 550 degrees C. Stainless steel plates offer stronger magnetic coupling and higher stirring force, preferred for dense suspensions or high-viscosity liquids. Aluminum plates heat and cool faster than ceramic, making them suitable for applications requiring rapid temperature changes. PTFE-coated plates are chemically resistant but limited to lower temperatures.
Temperature range and accuracy
Standard combination units reach 300 degrees C to 380 degrees C on the plate surface. Digital PID-controlled units with an external temperature probe monitor actual solution temperature (not plate temperature) and maintain the solution within plus or minus 1 degree C at setpoint, which is important for temperature-sensitive enzyme reactions, crystallization protocols, and culture media preparation. Analog units without external probes rely on plate surface temperature, which can differ significantly from solution temperature.
Stirring speed and stir bar volume
Stirring speed ranges from 100 rpm for gentle mixing to 1500 rpm for vigorous suspension. Match stir bar size to vessel volume: a 10 mm bar for tubes and small vials, a 25 mm to 40 mm bar for 50 mL to 500 mL beakers, and a 50 mm to 80 mm bar for 1 L to 5 L vessels. Using a stir bar too large for the vessel prevents rotation; too small causes inefficient mixing.
Safety features
For work with flammable solvents, specify an explosion-proof or EX-rated hotplate with enclosed heating elements that do not produce sparks. Digital models with over-temperature alarms and contact temperature sensors on the plate surface prevent runaway heating events. Some models include motor auto-shutoff if the stir bar decouples, reducing the risk of unattended overheating.
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<h2>Specifications Context</h2>
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Maximum plate temperature (300 to 550 degrees C) is a surface rating; actual solution temperature depends on vessel geometry, fill volume, and heat loss. Use an external temperature probe (PT1000 or thermocouple) inserted into the solution for accurate setpoint control. Plate dimensions (typically 135 mm x 135 mm to 300 mm x 300 mm) determine the vessel sizes the unit can safely support; oversized vessels extending beyond the plate perimeter are unstable. PTFE stir bars should be inspected for wear periodically, as chipped PTFE releases particles into the solution; replace any stir bar showing surface damage.&nbsp;
&nbsp;
Ready to stir things up? Take a look through our hotplate and stirrer collection and <a href="https://mbpinc.net/contact-us">reach out to the MBP team</a> for a friendly quote today.

Hotplate & Stirrers

Optional Rod for Hotplate/Stirrer (H3770 Series)

Optional Temperature Probe (H3770 Series)

Clamp Set for H3770

Clamp Set for H3770 (Chemically Resistant/Inert Teflon)

Digital Hotplate Stirrers (10 x 10″) Series

The Digital Hotplate Stirrers (10 x 10 inch) Series by Benchmark Scientific is a 10 × 10-inch digital hotplate magnetic stirrer with a chemical-resistant white ceramic plate, 35–400°C temperature range, 150–1500 rpm speed range, and 15 L maximum stir capacity. It runs at 120V/750W with a large digital display, a 50°C safety LED, and optional external probe support for ±1°C sample accuracy—backed by a 2-year warranty. Available models: H3710-HS, H3710-HS-E, H3710-H, H3710-H-E, H3710-S, H3710-SE.

Dimensions (w x d x h)

Digital Hotplate Magnetic Stirrer, 10 x 10 inch, 115V

Digital Hotplate Magnetic Stirrer, 10 x 10 inch, 230V

Digital Hotplate, 10 x 10 inch, 115V

Digital Hotplate, 10 x 10 inch, 230V

Magnetic Stirrer, 10 x 10 inch, 115V

Magnetic Stirrer,  10 x 10 inch, 230V

Digital Hotplate Stirrers (7 x 7″) Series

The Digital Hotplate Stirrers (7 x 7 inch) Series by Benchmark Scientific is a digital hotplate magnetic stirrer with a 7 × 7-inch ceramic work surface, heating from 35°C to 400°C and stirring from 150 to 1,500 rpm for up to 5 L. Digital display, safety LED hot-surface indicator, external temperature probe input (±1°C control), and a 2-year warranty. Available in 120 V or 230 V. Available models: H3770-HS, H3770-HS-E, H3770-H, H3770-H-E, H3770-S, H3770-SE.

Digital Hotplate Magnetic Stirrer, 7x7 inch, 115V

Digital Hotplate Magnetic Stirrer, 7x7 inch, 230V

Digital Hotplate, 7x7 inch, 115V

Digital Hotplate, 7x7 inch, 230V

Magnetic Stirrer, 7x7 inch, 115V

Magnetic Stirrer, 7x7 inch, 230V

HCS-50L / HCS-150L Hotplate Shakers

High Capacity Magnetic Stirrers

The High Capacity Magnetic Stirrer Series by Benchmark Scientific is a 50-litre high capacity magnetic stirrer with a 11.8 × 11.8-inch chemically resistant ceramic top plate, 50–1500 rpm speed range (1 rpm increments), built-in timer up to 9 hours, and dual-voltage 120V/230V compatibility. Ideal for large-volume buffer preparation, reagent blending, and scale-up mixing. Available models: IPS7101-50, IPS7101-50-E, IPS7101-150, IPS7101-150-E.

High capacity magnetic stirrer, 50L with ceramic top plate, 120V

High capacity magnetic stirrer, 50L with ceramic top plate, 230V

High capacity magnetic stirrer, 150L with ceramic top plate, 120V

High capacity magnetic stirrer, 150L with ceramic top plate, 230V

Overhead Stirrers Accessories

<h2>What Are Overhead Stirrer Accessories?</h2>
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Overhead stirrer accessories are modular components that attach to an overhead stirrer motor unit to adapt it for specific applications, vessel formats, and chemical conditions. The core accessories are impellers (the mixing head), drive shafts (which connect the motor to the impeller), chuck or collet adapters (which secure the shaft in the motor's output), and support stands with clamps or crossbar assemblies that position the motor above the vessel at the correct height. Additional accessories include vessel holders and clamp stands for securing round-bottom or Erlenmeyer flasks during mixing, PTFE sleeves for shaft sealing in closed-vessel applications, and digital speed display controllers that retrofit onto analog motor units. Because overhead stirrer motor chucks accept shafts within a defined diameter range (commonly 6 mm, 8 mm, 10 mm, or 12 mm), confirm shaft diameter compatibility with the motor before ordering any impeller-and-shaft combination. Before ordering any accessory, confirm three things: motor chuck bore diameter, required shaft length for your vessel depth, and whether the impeller geometry matches the flow regime your application needs.
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<h2>What You Will Find:</h2>
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<ul>
<li>Stainless steel and PTFE (Teflon&reg;) propellers compatible with overhead stirrers for a variety of mixing applications.</li>
<li>One-line propellers designed for efficient agitation in low- to medium-viscosity liquids.</li>
<li>Paddle propellers with flat holes for enhanced fluid circulation and blending performance.</li>
<li>Centrifugal impellers that promote radial flow and effective mixing of liquid samples.</li>
<li>Four-arm propellers available in stainless steel or PTFE for versatile stirring across diverse laboratory workflows.</li>
</ul>
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<h2>How to Choose Overhead Stirrer Accessories</h2>
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Impeller geometry
Impeller type determines mixing regime and is the primary accessory selection decision. Propeller impellers (two- or three-blade marine propeller) generate axial flow, drawing fluid from above and directing it downward, suited for general liquid blending, cell suspension, and low-viscosity mixing. Paddle and anchor impellers sweep tangentially near the vessel wall, appropriate for high-viscosity materials that resist axial flow. Dispersing disc impellers (flat disc with serrated edge or teeth) generate radial high-shear flow for emulsification, pigment dispersion, and fine particle suspension. Ribbon impellers are used for highly viscous, thickening batches where conventional impellers fail to move material from the vessel walls.
Shaft length and diameter
The shaft length must extend from the motor chuck to the correct immersion depth in the vessel. Standard lengths range from 200 mm to 600 mm; longer shafts are available for deep vessels or pilot-scale bioreactors. Shaft diameter must fit within the motor's chuck bore (confirm before ordering). Thicker shafts (10 mm to 12 mm) are more rigid and reduce wobble at high speed; thin shafts (6 mm) suit small-volume vessels and lower-torque motors.
Material: stainless steel vs. PTFE
Stainless steel (316L is preferred for chemical resistance over 304) is the standard for shafts and impellers in aqueous buffers, culture media, alcohols, and mild organic solvents. PTFE shafts and impellers are required for corrosive acids, bases (concentrated NaOH, HCl, HF), halogenated solvents, and any application where metal ion contamination of the sample must be avoided. Stainless steel and PTFE impellers are not interchangeable from a torque-transfer standpoint; PTFE is softer and suitable for lower-torque applications.
Support stands and clamps.
Support stands must be rigid enough to prevent shaft wobble at maximum operating speed. Confirm that the stand's vertical travel range accommodates the vessel height plus the motor unit. Crossbar clamp assemblies allow the motor unit to be raised and lowered without removing the shaft from the vessel. Heavy-duty stands with a wide base footprint are recommended for motors above 40 Ncm and for operation above 500 rpm.
Chuck and collet adapters
Motors accept shafts with a specific bore range. Collet adapters reduce or increase the effective chuck bore to fit a different shaft diameter. Confirm the motor's chuck diameter (manufacturer-specific) and the shaft outer diameter before ordering a collet or chuck adapter; a mismatched fit can cause shaft slippage during mixing.
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<h2>Specifications Context</h2>
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Impeller diameter should be 30 to 50% of the vessel inner diameter for most mixing regimes. A blade diameter that is too small leaves dead zones at the vessel wall; too large generates excessive shear and can damage shear-sensitive samples. For autoclave-compatible setups, confirm that the shaft, impeller, and any sealing sleeve are rated for 121 degrees C steam sterilization. Shaft straightness should be verified at the stated operating speed; a bent or unbalanced shaft generates vibration that compounds with any sample viscosity increase to stress the motor bearings.&nbsp;
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Looking for the right propeller for your process? Explore our overhead stirrer accessories and <a href="https://mbpinc.net/contact-us">reach out to the MBP team</a> for a quote today.

Overhead Stirrer Accessories

IPS2050-P-S4 by Benchmark Scientific is the 316 stainless steel 4-arm propeller (400 mm length, 50 mm diameter, 8 mm shaft) included as standard with the Benchmark IPS2050 OS-20L and OS-40L overhead stirrers. Designed for mid to high-speed mixing, it generates strong radial flow across the IPS2050's 30–2,200 rpm operating range.

Length

Diameter

Shaft Diameter

Material

MiniMag Magnetic Stirrers

Benchmark Scientific S1005 MiniMag Magnetic Stirrer is a compact magnetic stirrer with a 4.7 × 4.7 × 1.2 in. footprint, 100–1,500 RPM analog speed control, up to 1.5 L capacity, and +4°C to +65°C operating range. 2W, 100–240V, 0.45 lbs — for cold rooms, incubators, and space-constrained benches. Available in 110V and 240V configurations.

MiniMag Magnetic Stirrer, 100V

MiniMag Magnetic Stirrer, 240V

<h2>What Are Multi-Position Hotplate Stirrers?</h2>
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Multi-position hotplate stirrers are magnetic hotplate stirrer units with 4, 5, 6, 8, 10, or 15 individual stirring positions arranged on a single heated work surface, each position driving its own PTFE stir bar independently. Each position supports a vessel (typically up to 400 mL to 1 L per position), and most models allow each position to be operated at the same shared speed and temperature setting or, on advanced models with independent position control, at individually programmed conditions. Multi-position units eliminate the throughput bottleneck of single-position stirrers in labs that routinely run parallel reactions, QC batches, dissolution testing, media preparation, or student laboratory exercises. Ceramic-coated top plates on most models resist chemical spills and provide even heat distribution across all positions. Models with brushless DC motors, LCDs, independent per-position speed and temperature control, built-in timers (1 to 999 minutes), and Pt100 external probe inputs for liquid temperature control are commercially available. Choose a multi-position hotplate stirrer when you regularly run the same protocol on 4 or more samples simultaneously; it improves consistency by running all samples in the same run rather than sequentially.
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<h2 dir="ltr">What You Will Find:</h2>
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<ul>
<li dir="ltr" aria-level="1">
5-position hotplate stirrers let you heat and mix multiple containers at once, perfect for synchronized testing.
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<li dir="ltr" aria-level="1">
Multi-functional stirring units feature durable top plates that ensure uniform heat across every single position.
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<li dir="ltr" aria-level="1">
High-capacity multi-stirrers provide the powerful torque needed to keep several solutions moving smoothly for hours.
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<li dir="ltr" aria-level="1">
Space-saving designs help declutter your workstation by replacing multiple individual units with one sleek machine.
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</ul>
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<h2>How to Choose a Multi-Position Hotplate Stirrer</h2>
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Number of positions
Configuration options run from 4 positions (common for parallel reactions in small labs) to 6, 8, 10, and 15 positions for high-throughput QC or dissolution testing. Confirm total bench footprint: a 10-position unit is significantly larger than a 4-position unit, and the instrument must fit within available bench space while leaving adequate clearance for vessel handling.
Independent vs. shared control
Entry-level multi-position units share a single speed and temperature control across all positions, which suits workflows where all samples run under identical conditions. Advanced models allow each position to be set to an independent speed and temperature, enabling gradient experiments or multi-protocol batch runs on a single unit. For dissolution testing and QC protocols that require documented identical conditions across all vessels, shared control with a single setpoint is preferable for simplicity and traceability.
Temperature range and uniformity
Most multi-position hotplate stirrers cover ambient to 120 degrees C (suitable for most aqueous biological and chemical workflows) or up to 300 degrees C on specialty high-temperature models. Temperature uniformity across all positions is more critical than in single-position units because inter-position temperature gradients directly affect data consistency in parallel runs. Ceramic-coated plates improve uniformity compared to stainless steel across wider multi-position surfaces.
Speed range and stirring volume
Speed ranges from 300 rpm to 1500 rpm, covering the majority of multi-position mixing applications. Confirm the maximum volume per position (typically 400 mL to 1 L) and whether a PTFE stir bar appropriate for the vessel size is included or must be purchased separately.
Timer and safety features
Built-in timers (1 to 999 minutes with an infinite mode) are a practical feature for dissolution testing and timed reaction protocols. Over-temperature protection and dry-run prevention (heat-warning LED or alarm) protect reagents and equipment during unattended operation. Closed top-plate designs that protect internal mechanisms from spills improve longevity in busy QC and teaching environments.
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<h2>Specifications Context</h2>
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Stir bar size matters on multi-position units: use the largest stir bar that fits the vessel without contacting the sides, as a bar that is too small at a shared speed setting may not mix effectively in larger vessels. Ceramic-coated top plates resist most laboratory acids and bases but should not be used with HF or strong oxidizers that attack ceramic surfaces. For pharmaceutical dissolution testing under USP standards, confirm that the unit meets the temperature uniformity and speed accuracy requirements of the applicable compendial method before specifying it as a dissolution apparatus substitute.
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Ready to multiply your results? Explore our multi-position hotplate stirrer range and <a href="https://mbpinc.net/contact-us">reach out to the MBP team </a>for a friendly quote today.

Multi-Position Hotplate Stirrers

Mult-Functional 5-position hotplate stirrer

H3715 Multi-Functional 5-Position Hotplate Stirrer by Benchmark Scientific provides simultaneous heating and magnetic stirring of up to five samples for parallel synthesis, dissolution, and incubation workflows. Available as H3715 (115V) and H3715-E (230V).

Temp Range

Positions

Bottle Capacity

Warrant

Mult-Functional 5-position hotplate stirrer,120V

Mult-Functional 5-position hotplate stirrer,230V with EU Plug

The Benchmark Scientific IPS7000 Multi-Position Hotplate Stirrer Series offers 3-, 5-, and 10-position configurations with a chemical-resistant ceramic platform (100 &times; 100 mm), heating from 35&ndash;120 &deg;C and stirring from 150&ndash;1,500 RPM. Its compact 8 &times; 9 in footprint fits biosafety cabinets and crowded benchtops, making it a practical choice for labs that need precise, simultaneous heat and agitation for volumes up to 1 L. Available models: IPS7000-3 (3-pos, 120V), IPS7000-3-E (3-pos, 230V), IPS7000-5 (5-pos, 120V), IPS7000-5-E (5-pos, 230V), IPS7000-10 (10-pos, 120V), IPS7000-10-E (10-pos, 230V).