This version of the premium key receiver lock features 100 Percent stainless steel and provides instant security for your camper, boat or trailer by securing your vehicle receiver hitch. Features patented 1/4 turn technology that cannot be false locked. A receiver pin is used to secure the receptacle part of a trailer hitch (attached to a vehicle) to inserts such as ball mounts, drawbars, accessory carriers or ornamental receiver plugs. The most common receiver pins are 1/2 Inch and 5/8 Inch in diameter. Class II receiver hitches have 1-1/4 Inch receptacles and use 1/2 Inch pins. Class III, IV and V receiver hitches have 2 Inch receptacles and use 5/8 Inch pins.