TRAILER COUPLER LOCK WITH INTERCHANGEABLE ADAPTER

A trailer coupler lock includes a shell, a coupler engagement plug, a locking mechanism and an adapter. The shell includes a cove configured to receive a receptacle of a trailer coupler, a plug channel in which a plug moves linearly from extended position to a retracted position, and a lock channel in which a locking mechanism is movable from a locked position to an unlocked position. In the locked position, the locking mechanism engages and secures the plug in an extended position with a portion of the plug extending from the channel into the cove. The cove includes a slot in which an interchangeable adapter is removably received. The adapter defines a slot for receiving a portion of a trailer coupler, e.g., the flange at and around the coupler receptacle.