This EverStart 6/12 Volt Circuit Tester dependable tool allows you to test fuses and light sockets, find broken, or live wires with this. This device tests for low voltage circuits and can be used with most 6, 12, and 24 Volt polarities on auto systems. Includes a quickly identifiable red and green light that indicates a positive or negative charge. At .25 lbs, the items small design is perfect for storage in vehicles and portability. Tester includes a metal probe for long lasting durability. To use locate a suitable ground or circuit and attach clip. Then locate wire to be tested and pierce able.