Heininger  6001 Advantage SportsRack 2" Threaded Receiver Trailer Hitch Lock
Threaded 2" receiver trailer hitch lock is great for locking your bike rack to the hitch. Hitch lock has a 0.625" diameter and works for all 2" receivers. For class III or class IV receivers. Threaded bolt provides the anti-wobble needed to keep your trailer or bike rack secure. Comes with 2 Keys. Covered key opening. Easy key insertion and removal. Weather resistant lock.