WIDE APPLICATION: The three-hole plug has a wide range of applications. It works great with trailers, tractors, farm machinery, utility vehicles, recreational vehicles, caravans, trucks, motorhomes, boats, etc. FUNCTION: The 12V 3-pin trailer plug is used to provide a stable connection for the lighting circuit between the tractor and the trailer, caravan, etc. The trailer plug is used to easily connect the lights to the trailer. PLUG & PLAY: Plug and play, easy to install. SUPERIOR QUALITY: 3-pin plug with a waterproof silicone rubber seal; the contact pin has good conductivity, and the plastic casing prevents rust and corrosion, ensuring safe and reliable performance. REPLACEMENT: The 12V 3-pin trailer plug is a perfect replacement for your old one; it can easily replace old and damaged plugs.