7-Way RV Boat Blade Trailer Light Circuit Wiring Tester Connector Adapter Plug

7-Way Blade Trailer Light Wiring Circuit Tester Round Adapter Pin Plug RV. 12V:Auxiliary(12V+)(Tester should stay lit at a constant). 7 WAY TESTER. Plug the tester into vehicle's mating plug. TM: Taillights(Turn on running lights.Tester should stay lit at a constant).

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