Heavy Duty ConstructionStarpy has one piece knob craft, stainless steel column door knobs are perfect hand touch, with rectangle zinc rosette 4 x 2-1/2 inch, is contemporary style for you. Entrance FunctionExterior door knob with deadbolt lock for entry door, 3 pcs brass keys assure secure and durable usage for two aspects. For exterior: Use key to Lock or unlock by deadbolt bolt only,door knobs always can turn. For interior: Interior deadbolt locked or unlocked by thumb turn,while door knob can lock by push button for double security.Interior knobs twist to released lock without key. Standard Backset & LatchStarpy privacy door knob fits backset 2-3/8 to 2-3/4 inch, use the adjustable zinc latch 45 degree turning. Easy & Fast InstallationThese three functions interior door knobs are convenient installed by screw driver, the rosette with exposed screw hole, tighten the screws directly or interior knob can be disassembled by the tool optional. Quality WarrantyStarpy off