For testing light circuits on vehicles, trailers and caravans The plug goes directly into a 7-pin N-type plug or socket, allowing for a pass-through test for all lighting circuits. Requires a 9V battery (not included) Vehicle test: Connect the tester to the vehicle socket. Turn on the ignition. The lights on the tester will illuminate if the function is working correctly. Trailer test: Connect the tester to the trailer socket. Press the yellow test button. The lights on the tester will illuminate if the function is working correctly. Type Article Version electrical connection parts Width 58.5 mm Width 5.85 cm Main colour blue Length 22.4 cm Length 0.224 m Current consumption Volt 12.0 V Type 7-pin Variant test plug