Adams Rite 4900 Heavy Duty Deadlatch Less Strike

Flexibility of traffic control. A reverse turn of the key while bolt is held retracted retains the bolt, to allow 2-way traffic for applications which require free entrance at times and exit-only at other times.
Interchangeable, without stile modification, with any MS1850A or MS1850S deadbolt of same back-set and face-plate shape.