1. Versatile Car Circuit Tester: The car circuit tester can be widely used for continuity testing; voltage polarity testing; light checking; motor checking; tracing and identifying short circuits and ground fault testing. It ensures accurate results 2. Flashlight: The car power tester has a built in flashlight. Only put the red and black clips over the positive and negative clips on the car battery to use the electrodes, making it easy to test and repair in the dark, or use it as a lighting lamp 3. : Electrical system probe tester to the vehicle's battery, the automotive technicians can conduct positive and negative battery current to the tip by cranking the power switch forward or backward 4. Polarity Output Test: Without pressing a button on the tester, use the probe on the front of the automotive circuit tester to detect an unknown polarity on the vehicle and check if it is charged