Abstract: A safe has a generally cylindrical chamber having at one end an access opening in which a closure can be located. Peripheral grooves around the closure and the access opening are aligned when the closure is in position. A sliding bolt in the closure can displace a ring which is captive in one of the grooves to an eccentric position relative to the opening, in which position the ring engages both of the grooves around approximately half of their peripheries to lock the closure in the opening.