Auditory Conductivity Indicator, 1 Each

The United Scientific® Auditory Conductivity Indicator by United Scientific is a reusable classroom tester that signals solution conductivity with a buzzer instead of a light. The more free ions a solution contains, the louder it sounds, making electrolyte comparisons easy for a whole class to hear. It has an on/off button with an LED and runs on a 9V battery (not included). Used in chemistry and physical science teaching labs.