Performance complies with ANSI (American National Standards Institute) A156.5, Series 2001, Grade 1 light commercial auxiliary lock. UL (Underwriters' Laboratories) rated. 3 hour fire door. 5 pin solid brass cylinder, keyed 5-pin, C keyway, keyed different. 2 brass cut keys per lock. Door range: 1-3/8" - 1-3/4". Adjustable backset. Strike: 1-1/8" x 2-3/4", 1/4" radius corner, strike number 10-116. Door frame strike reinforcer with 3" screws. Deadbolt thrown or retracted by key from outside or by inside turn piece. Bolt automatically deadlocks when fully thrown.