【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. 【Comprehensive Testing】Quickly verify six essential lighting functions, tail lights, brake lights, reverse lights, turn signals, electric trailer brakes, and 12V auxiliary power, for fast and accurate diagnostics.
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