Tylo Entry Smt Satin Chrome Bx 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