The yale pm322 3 lever mortice deadlocks offer a standard level of security and are suitable for use on internal timber doors the deadbolt is locked or unlocked by key from either side these deadlocks also have a 13mm anti saw deadbolt and have a 10 year guarantee a deadlock has a single deadbolt which is locked or unlocked and locked by means of a key from either side whereas a sashlock has both a deadbolt and a latch which is operated from either side by a lever handles the security level of m