For keyed exterior doors. Both bell-shaped knobs lock or unlock by key outside or turnbutton inside. DOOR PREP: 2-1/8" Cross Bore, 1" Edge Bore, 1" x 2-1/4" Latch Face. BACKSET: 2-3/8" standard and adjustable 2-3/8" and 2-3/4" optional. DOOR THICKNESS: 1-3/8" to 1-3/4" . CYLINDER: 5-pin. FACEPLATES: 1" x 2-1/4" round corner. STRIKES: 2-1/4" full lip round corner. BOLT: 1/2" throw. HANDING: Reversible for right or left hand doors. ANSI/BHMA: Grade 3.