Double cylinder lock case with an automatically deadlocking latchbolt. The deadlocking is controlled by a snib in the frontplate. Snib position: UP = Deadlocking, latchbolt protrudes 21 mm. The lock canbe opened only with a key or a thumbturn. DOWN = Latchbolt protrudes 14 mm. The lock can be opened also with lever handles. LC121X is the microswitch version of the lock. The switchchanges it’s status when the latchbolt leaves its day locking position, i.e. the bolt protrudes 15 mm or more. Striker plates to be used with a microswitch locking box: 4692, 4693. Striker plate 4690, 4691, LP711, LP714, LP721, LP731 Cylinder ABLOY® C, N, T, U Fire resistance Yes