1Excellent Function: The high quality electric circuit probe tester is especially designed to reduce diagnostic time in automotive electrical systems, assist to repair your vehicles fast and convenient. 2Convenient Operation: The electric circuit tester comes with about 4m long cable, which is less constrained by distance during the operation, and can deliver you a more easier testing process. 3Current Conduction: Automotive technician can conduct a positive or negative battery current to the tip by rocking the power switch forward or backward after simply connected to your car battery. 4Short Circuit Protection: The power circuit probe tester is a comprehensive 624V DC test kit features short circuit protection and can test for bad ground contacts instantly. 5Ground Lead Design: The electrical system diagnosis tester tool allows you to track and locate short circuits, and can test for continuity with the aid of its auxiliary ground wire.