Coffin lock

Coffin Lock is a slang term for a blind panel connector (also called a Butt-Joint Fastener) often used in the performing arts to join together stage decks or scenery in a butt joint or cabinet and lid locks on road cases. These are typically two part connectors (male and female) that draw together and lock. The two most common types are the cam and acceptor (sold under the trade name "Roto-Lock") and more traditional hook and pin version. These devices generally use an Allen key to operate the locking mechanism via a small diameter hole either through the face or rear of the panel. When locked, the considerable mechanical advantage offered by the cam or hook holds the panels tightly together. Coffin locks can be installed directly into a mortise cut into each panel for total concealment except for the locking hole or mounted to the rear of the panels.