Boat trailer kits typically include a sturdy frame to hold the boat, fenders to protect the trailer from debris on the road, required lights for Department of Transportation compliance, a coupler to attach the trailer to a vehicle, and wheels. Owners must assemble these components using their own hand tools, although many kits also include a hardware package with the required fasteners.
Most boat trailer kits feature frames that have specific weight guidelines. The weight listed on the kit is often the maximum weight the trailer can handle, including any accessories inside the boat. Fenders enhance the appearance of the frame while providing additional support and keeping dirt and dust on the road from kicking up into the trailer. This helps protect the boat from hazards on the road.
Boat trailers must comply with DOT regulations regarding towed watercraft, which mandate a series of lights that connect to the taillights of the vehicle to provide turn signals and indication of braking to cars following behind the towed boat. A coupler, often molded onto the frame or provided as a separate piece, allows the trailer to connect with the trailer hitch on the towing vehicle, and the wheels included with the kit must also meet DOT restrictions and move freely. More advanced kits include specialized hydraulic brakes for use with heavier watercraft and customized axle pads.