1Function: The adapter connector cable converts a 7 way round socket to a 4 way flat socket for easily syncing trailer signals and taillights without rewiring. 2Material: The plug adopts copper pin contacts for better electrical conductivity. Plastic shell, waterproof, wear resistant, flame retardant, cold resistant, extremely durable. 3Fine Workmanship: With a total length of 0.9m, professional manufactured, exquisite workmanship with unique design, ensure stable performance and high reliability. 4Application: Widely used in most towing vehicles including trailer, caravans, tow trailers, semi trailers, motorhomes, etc. with Us 7 to 4 pin trailer adapter. 5Easy Operation: Easy to install, no need to rewire, plug and play, very convenient. Easy to install the adapter cable between trailer cord and trailer plug.