Conductivity Tester, 1 Each

The Conductivity Tester by United Scientific is a handheld device that shows the relative conductivity of solutions, acids, salts and solids on a 1 to 10 scale of green LEDs. Two 53 mm brass probes are touched to a solid or immersed in a liquid, and the unit runs on an included 12V 23A battery. Chemistry and physical science teachers use it for quick student comparisons of electrolytes and conductors.