It is necessary to make a slot at the level at the level at the level at which the lock will be installed. Special racks made of woods for doors are clogged into a metal profile. Then the loop profile is welded to the box and loops. Then a metal sheet is welded. Then all welding seams are protected, the lock is mounted.As a rule, a pair of locks is installed. Then the door of the eye is mounted and door trim is carried out.