It is characterized by the ability to lock the door inside, with an emergency opening device on the outside, and a red or green display, or a small handle lock with the "someone" or "no one" display or the same function ball lock.
- Mar 31, 2019-
It is characterized by the ability to lock the door inside, with an emergency opening device on the outside, and a red or green display, or a small handle lock with the "someone" or "no one" display or the same function ball lock.