It consists of a sharp probe housed in a transparent handle with an internal indicator bulb, a coiled grounding wire, an alligator clip, and a replacement fuse. Mechanically, it is used to quickly diagnose electrical faults in cars, trucks, and boats by clamping the alligator clip to a known ground source (or power source) and touching the sharp metal probe tip to a wire, fuse, or connector. If electrical current is successfully flowing through the circuit, the internal bulb lights up, allowing you to instantly identify blown fuses, short circuits, broken wires, or faulty ground connections without needing a complex multimeter.
