Wide range applications: EM285 circuit tester can be used to test continuity, test polarity of a voltage, check lamps, check electric motors, locate short circuits, and test for bad ground contacts. Long test lead: The cable length is approximately 16 feet, allowing easy testing of various electrical systems. Short-circuit protection: The unit includes short-circuit protection and enables instant detection of poor ground connections. Easy operation: After connecting the unit to the vehicle's battery, an automotive technician can apply positive or negative battery current to the tip by moving the switch forward or backward. Comprehensive 6-24V DC test kit: Designed for use with DC voltage only; do not use on AC voltage. Operation Instructions: Unroll the unit's cable. Attach the red clip to the positive terminal of the vehicle's battery. Attach the black clip to the negative terminal of the vehicle's battery. Operating Voltage: 6-24V DC Overload Protection: 8A (The device will automatically disconnect if the current exceeds 8A.) Color: Black + Red Material: Plastic + Metal Package Contents: 1 x Circuit Tester Note: Other items are not included. Note: Lighting and display settings may cause slight variations in color between the image and the actual item. Measurement error is +/- 1-3 cm.