This 5/8-inch dead bolt is designed for all 2" receivers to prevent theft of the receiver or whatever you are towing. And don't forget the coupler lock to prevent the trailer from being removed off the ball. Both are made of chrome-plated machine-hardened steel, and approved for saltwater use. Easy turn opens the lock, which can't pop open or be falsely locked. A must for 2" Hitches, Receiver Covers, Bike Racks and Cargo Platforms. Learn More