- LED DIGITAL DISPLAY AND ACCURATE READING: The Power Circuit Probe Kit features an LED digital voltage display for accurate volt readouts. Bidirectional current and voltage testing mode allows attaching the alligator clamp to either negative or positive ground. Red light indicates positive polarity; green light indicates negative polarity. LED visibility is not affected by ambient light, so readings are readable in daytime or dark areas. - COMPUTER SAFE DESIGN: Insulation protective cover provides a better grip on the body and screws and offers insulation against electric shock. The circuit board includes line protection for safer operation and greater burn resistance. - FLEXIBLE TO USE AND CARRY: Extra long 96 inch PU spring wire increases flexibility, range, and ease of testing. A sharp stainless steel probe with protective rubber tip can reach into tight places and pierce insulation. Compared with cable wires, coil spring wires are lighter and easier to carry, taking up less space in your toolbox or storage area. - WIDELY USE AND APPLICATIONS: This professional automotive heavy-duty circuit test light is designed to test 2.6-32V DC. It can detect power, ground, and identify shorts and breaks in wires. Use it to check automotive headlights, taillights, turn signals, faulty sockets, connections, fuses, broken wires, and more. Practical scenarios: verify headlight circuits for power and ground; diagnose taillight or turn-signal circuit faults; locate shorts or broken wires in an automotive wiring harness.