Schlage FB55N V GEO 619 CAM Camelot Single Cylinder Georgian Decorative Entry Set Knob, Satin Nickel Security set contains 1 deadbolt and 1 keyed entry Single cylinder deadbolt operates with a key on the exterior and a thumb turn on the interior For use on exterior doors where additional security is needed Ansi/bhma Grade 1 security deadbolt meets the highest industry Standards Biggest bolt diameter for maximum kick-in resistance and hardened Steel deadbolt core that spins to resist saw attacks