The patented “Breakthrough One-Key Lock Technology” of BOLT Locks is a security option for protecting trailers, hitches, boats, ladders, kayaks and more. BOLT Locks use specially crafted tumblers to memorize a vehicle’s ignition key the first time it is inserted into the lock. One complete turn of the key moves the tumblers to fit that one specific key, resulting in a uniquely programmed lock. The stainless steel pin of the Coupler Pin Lock fits couplers from 1/2-inch to 3 3/8-inches in 1/8-inch increments. BOLT’s coupler pin lock secures the locking lever from any movement and serves dual purposes: locking a trailer ball when hitched to a vehicle or making the coupler unusable when off of the vehicle. When the trailer is not hitched to a vehicle, the coupler pin lock secures the locking lever so that it cannot be moved in order for a new vehicle to attach a ball mount to the trailer. The BOLT Receiver Lock is the other dual purpose lock for towing. Designed to lock the ball mount receiver onto the hitch of the vehicle, the Receiver Lock comes in two sizes: 1/2-inch and 5/8-inches.