Check the listing for details. 4 Pin Flat to 7 Way RV Trailer Truck Adapter Wiring Plug with Mounting Bracket. Color: Black, Condition: New. Listed at 13.49 USD. Features 1. Make the Wiring Easier - Plug and play, convert the car's 4-pin flat socket to the 7-pin blade round socket for the trailer, synchronize the trailer's signal light, and customize the plug-in wiring system to connect the trailer, which is very convenient and solves the trouble of rewiring every time2. High-quality Manufacturing - Using pure copper as the inner core, greatly improves the electrical conductivity. With the high-quality PVC shell, wear-resistant, corrosion-resistant, effectively waterproof and long service life3. Provide Extra Protection - With the spring-loaded cover, high dust-proof, to avoid the adapter damage from the external environment when it is not in use4. Simple to Install - Equipped with mounting bracket, screws, and nuts, just find the right position to install and tighten the nut to install successfully5. Wide Application - Applicable to towing all vehicles that don't require electric brakes, including trailers, semi-trailers, RVs, etc Is the wiring system of the original synchronous trailer too complicated? Don't worry, the MICTUNING 4-way flat to 7-way round adapters customize the plug-in wiring system for you to connect the trailer! It converts the 4-pin flat socket to the 7-pin blade round socket, plug and play, and easily synchronizes the trailer's taillights and turn signal lights. Made of 100% copper, combined with a strong PVC casing, has excellent electrical conductivity, wear-resistance, corrosion-resistance, and is extremely durable. With spring-loaded protective cover, it is dust-proof and moisture-proof, providing better protection for the adapter plug. Widely used in most towing vehicles, including trailers, semi-trailers, RVs, etc. NOTE: - It does NOT support electric brakes, and doesn't handle with charging circuit. Package Included: 1x trailer adapter plug 1x mounting bracket 6x screws 6x nuts