Easier Wiring - Plug and play, convert flat 4-pin car plug to 7-pin round plug for trailer, synchronize trailer signal light and customize plug-in wiring system to connect trailer, which is very convenient and solves the problem of rewiring every time High Quality Construction - Using pure copper as the inner core greatly improves electrical conductivity. With the high quality PVC shell, wear-resistant, corrosion-resistant, effectively waterproof and long service life Provides extra protection - With the spring-loaded cover, very dust-proof, to prevent damage to the adapter from the outdoor environment when not in use Simple to install - Equipped with mounting bracket, screws and nuts, simply find the right position to install it and tighten the nut to install it successfully < p>Wide Application - Applicable to all towing vehicles that do not require electric brakes, including trailers, semi -trailers, motorhomes, etc.