ITEM NAME:Trailer Hitch Coupler Small Lock Zinc Alloy 1/4 Inch Pretty C5G4 K4Z5 2COLORS,.Security Of Our Coupler Locking Pin: This trailer lock is made of high-strength steel to deter theft. The hitch lock is coated with black electrophoretic paint to prevent corrosion. Coupler Locking Hitch Pin's Application: Tow Trailer Boat RV Truck Car.