The yale pm246 2 lever mortice sashlocks offers 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 sashlocks also have a 125mm deadbolt and are suitable for use on internal doors where privacy is required a deadlock has a single deadbolt which is 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