7- and 4-Way Circuit Tester

Tests power supply from tow vehicle to trailer. Tests both 7-way round and 4-way flat tow plugs. Simply plug into vehicles tow plug and operate lights, brakes and turn signals to test circuits. Speeds trouble shooting time and shows if vehicle is properly wired. This is a tester only. 4-Way Flat Capable: Yes, 6-Way Round Capable: No, 7-Way Round Capable: Yes, Tests Turn Lights: Yes, Tests Brake Lights: Yes, Tests Tail Lights: Yes