【Function】Easily test both 4 pin and 7 way Trailer Connector Tester with this versatile 2 in 1 trailer light tester, simplifying trailer circuit checks on most trucks. 1 Trailer Light Tester. 【Adapter Compatibility】Effortlessly convert your vehicle’s 7 pin output to a standard 4 pin flat adapter, making it simple to connect and test 4 way trailer light plugs.
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