Mortise locks

 

— the lock is installed in a niche from the end of the door; when installed, it turns out to be hidden inside, only a keyhole and a rotary knob (if any) are located outside. They are used in a wide variety of areas — from residential premises to warehouses, garages, etc. Such locks are highly reliable: it is very difficult to knock out or break out a mortise lock, it is often easier to break the door itself. At the same time, installation often does not present any particular difficulties, since niches for mortise locks may initially be provided in the doors (this is especially true for apartment metal doors). On the other hand, if there is no such niche, then its preparation can be quite laborious and troublesome.