Abstract: A slide-bolt type latch locking means is disclosed including a rotary member mounted on a shaft for engagement with a latch bolt to hold the latch bolt in locked condition; a rubber washer is compressed by the rotary latch lock and prevents rotation of the latch lock by vibration of the supporting member to maintain the latch lock in position but permitting manual rotation of the latch lock to permit unlocking of the latch-bolt. Another embodiment employs a rotary latch lock mounted on a slide bolt with a radial slot alignable with a fixed lug to permit movement of the slide bolt to an opened condition, a movement not possible when the slot is not aligned with the fixed lug; a compressible washer maintains the latch lock in any given position of rotation.