The Multi-Voltage Glow Plug Tester from Strategic Tools & Equipment allows the diesel technician to perform testing on glow plugs of various voltage levels, up to 24V. This tool automatically selects the glow plug voltage and provides an immediate "yes" or "no" (pass/fail) indication for the technician. Because it can test multiple voltages, it replaces several single-voltage testers. The tool is powered by an internal 9V battery with a "low battery" warning. This tester contains an auto switch-off if the unit is not being used, to conserve battery power.