Flexibility of traffic control during and after business hours is offered by 4710 Series Deadlatches. A reverse turn of the key while bolt is held retracted retains the bolt, to allow two-way traffic for hospitals, banks, stores and other buildings which require free entrance at certain times and exit-only at other times. Interchangeable, without stile modification, with any MS1850A or MS1850S deadbolt of same backset and faceplate shape. (They do not, however, provide the same maximum security level as the MS Deadbolt.) Turn key or operate handle to retract spring-loaded latch bolt. To hold bolt retracted, push it in and secure by reverse turn of key. Uses any standard mortise cylinder with MS cam. Latch Bolt is 1/2" X 1" X 1/2" throw. All metal with hardened steel internal pins. Handing is easily reversible without special tools. Auxiliary Bolt all metal. Deadlocks latch bolt to prevent “loiding” or case-knife entry. Strikes sold separately see 4502 Cylinder Backset 7/8", 31/32", 1-1/8" or 1-1/2" only. Case Steel with corrosion-resistant plating, 1" X 5-13/16" X depth (depth varies with backset)