http://www.discountramps.com/locking-hitch-pin.htm
Replace a standard receiver pin with a high quality locking hitch pin to deter theft while keeping hitch ball mounts, hitch carriers, trailers, bicycle racks, and other hitch devices secure. Each locking hitch pin features a strip of knurled diamond pattern surface for added grip. Includes (2) keys and a rubber keyhole cap to reduce moisture buildup inside the lock. Sizes are available for 1-1/4" Class I/II or 2" Class III/IV vehicle hitch receivers. Made with a steel barbell construction, finished in polished zinc plate for added durability.
www.discountramps.com