12V Trailer Socket 12 V Trailer Accessories 7-Pin Socket 7- Pin Trailer Socket. Durable Brass Contacts: Pure copper points with nickel plating for excellent conductivity and corrosion resistance. Waterproof Design: Sealed housing protects against rain water and dust, ensuring reliable performance. Safety Lock Feature: Equipped with a safety lock to prevent plug movement caused by vibration during towing. Wide Compatibility: Accepts standard 7-way RV trailer connectors and a wide range of wire gauges. Multi-Function Connectivity: Connects taillights, brake lights, reverse lights, turn signals, and auxiliary power. OEM/ODM Support: Full customization, minor customization, and flexible customization services available.