[European] The small trailer plug simply plugs into the standard European style 13-pole socket and fits the other side into the 7-pin socket on most caravans/trailers. Note: The black one is the normal version which is for the European system (the). [13 Pin-7 Pin] 1 x 13 Pin Male - 12N & 12S 7 Pin Trailer Adapter. 13 pin to 7 pin conversion, connecting a car and trailer/caravan and supplying power to the trailer/caravan for all important indicators, signal and refrigerator. Ensure the electrics of the vehicle and caravan/trailer are compatible when towing. [Twin 7 Pin Electrics] The 7 pin 12N electrics provides legal lighting which includes brake lights, indicators and fog lights. The 7-pin 12S electrical provides additional lighting for backup lights, interior lights, and appliances. connection and make it easier to turn on all your electrical devices. [Easy to Install] Plug and Play, without cable is used to easily connect the vehicle lights to the trailer. Plug and play, plug the