Wide range applications: This circuit tester is suitable for testing continuity, checking polarity of a voltage, inspecting lamps, evaluating electric motors, tracing and locating short circuits, and testing for poor ground connections, among others. Long test lead: The cable measures approximately 16ft, making it easy to test any electrical system. Short-circuit protection: The device features short-circuit protection and can promptly test for faulty ground connections. Easy operation: After a quick connection to the vehicle's battery, automotive technicians can direct positive or negative battery current to the tip by toggling the power switch forward or backward. Comprehensive 6-24V DC test kit: Designed for use specifically with DC voltage; do not use on AC voltage. Operation Instructions: Unroll the unit's cable Clamp the red clip to the positive terminal of the vehicle's battery Clamp the black clip to the negative terminal of the vehicle's battery Operation Voltage: 6-24V DC Overload Protection: 8A (If the current exceeds 8A, this unit will automatically disconnect the current.) Colour: black + red Material: plastic + metal Package Contents: 1 * Circuit Tester Only the above package content, other products are not included. Note: Lighting and various displays may cause the color of the item in the picture to differ slightly from the actual product. The allowed measurement error is +/- 1-3cm.