Performance complies with ANSI (American National Standards Institute) A156.5, Series 4000. Grade 2 auxiliary lock, and ANSI A156.5, 2001 Series 4000 Grade 2. UL (Underwriters Laboratories) rated. 3 hour fire door. 6 pin solid brass cylinder, keyed 5-pin, C keyway. 2 nickel silver keys per lock, 5-pin, C section. Door range: 1-3/8" - 2". Adjustable backset 2-3/8 In. or 2-3/4 In. Strike: 1-1/8" x 2-3/4" square corner, T-strike. Door frame strike reinforcer with 3" screws. Turn button locking. Unlocked by key outside or by turn button inside. Inside knob always unlocked. In accordance with California Prop 65 WARNING: Cancer and Reproductive Harm-www.P65warnings.ca.gov ADVERTENCIA: Cancer y Dano Reproductivo-www.P65warnings.ca.gov AVERTISSEMENT: Cancer et Troubles d l'appareil reproducteur-www.P65warnings.ca.gov - Lead