A 4 wire flat is the most commonly used trailer . This is found on small boat, utility, , snowmobile, and small camper trailers where /brake, left turn/brake, /marker lights and ground is needed. This connectors are designed and manufactured to give you a reliable connection every time you in your trailer. Features - Color: Shown in the pictures. - Material: Plastic and copper. - Size: Approx. 83 x 3 x 1.5cm/ 32.7 x 1.2 x 0.6 inch (LxWxH). - Waterproof: Yes. - Splices into existing wiring to provide connections for both vehicle and trailer. - Looped wire can also be used as a wire extension for an existing connector. - flat output connects lights, brake lights and turn signals. - Constructed with bonded wires for easier installation. Package list: 1 x 4 Wire Flat Extension Flat Connector Socket for Trailer