This 12V 7 PIN 13 PIN CAR TRAILER TOWING LIGHTS WIRING CIRCUIT PLUG SOCKET TESTER SET by adapter-universe is essential for testing trailer towing lights. The tester includes functions for turn signals, brake lights, and rear fog lights, all of which are crucial for ensuring safety while towing. The package comes with a 1x trailer tester and a 9V battery is required for operation. The black tester is compatible with universal 7Pin to 13pin connectors, making it a versatile tool for any trailer.
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