Trailer Plug Socket Tester, EVERGD 12V 13 Pin Trailer Light Connector Cable Wiring Circuit Diagnostic Testing Tools Tester for Towing Car Caravan RV Cars Truck. This 13 Pin Trailer Light Tester can quickly indicate the circuit faults in the wiring circuit on the towing vehicle or trailer, the trailer light circuit tester requires 1PC 9V battery (not included).
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