Operated by key outside and turn piece inside. All metal components. Rust-resistant solid brass keyway for more security. Solid brass bolt with hardened steel rod insert to prevent sawing through. Cylinder drilled for construction keying. Door Prep: 2-1/8 in crossbore, 1 in edge bore, 1 x 2-1/4 in latch face. Door Thickness: Fits 1-3/8 or 1-3/4 in doors. Cylinder: 5-pin, removable, KW1 keyway, one piece solid brass; (2) nickel, solid brass keys. Strikes: 1 x 2-1/4 in. Bolts: Solid brass, steel reinforced, full 1 in throw. Handing: Reversible for right or left hand doors. ANSI/BHMA: Exceeds Grade 3 Standards. Adjustable Latch: Fits 2-3/8 to 2-3/4 in square corner, radius corner or drive-in applications; 1/4 in radius corner strikes.