Cal Royal NM8050 Mortise Office/Entrance Lock
Latch bolt retracted by key outside and inside lever when outside lever is locked. Outside lever retracts latch bolt unless outside lever is locked by operating toggle button. Outside lever is locked and unlocked by toggle button. Key outside locks outside lever only. When latch bolt is retracted by inside lever, outside lever remains locked. Auxiliary latch deadlocks latch bolt when door is closed. Inside lever is always free for immediate exit.