Lock or unlock by key outside, inside knob always free. All metal components. Solid steel deadlocking latch assembly. Rust resistant solid brass keyway for more security. Seamless one-piece knob for extra strength. DOOR PREP: 2-1/8" Crossbore, 1" Edge Bore, 1" x 2-1/4" Latch Face. DOOR THICKNESS: Fits 1-1/4" to 1-13/16" doors. CYLINDER: 6-pin, removable SC1 keyway, solid brass, one piece; re-keys to Schlage. With 2 nickel plated, solid brass keys. FACEPLATES: 1-1/8 x 2-1/4 STRIKES: 1-1/8" x 2-3/4" square corner T-strike. BOLT: Steel 1/2" throw. HANDING: Reversible for right or left hand doors. ANSI/BHMA: Grade 2. U.L. Approved 3-Hour Fire Rating.