7-Pin Towing Trailer Tow Bar Caravan Plug Socket Light Wiring Circuit Tester Hot
5X/Set 12V Glow Plug Chinese Diesel Heater Glow Plug Diesel Heater Glow Plug New. Just plug the tester in the 7 pin socket or the 7 pin plug of the trailer or caravan and press the yellow button on the side of the tester.