Tests elements and thermostats while they are in the heater. May also be used to test continuity in fluorescent lights, fuses and all appliances. Sensitive enough to measure even the fine filament wire in a light bulb. Sensitive LED light indicates continuity. Unbreakable body with protective cover over light and probe. More useful than a circuit tester. Complete instructions and batteries included.

Camco Water Heater Continuity Tester