Deadbolts The unique ABLOY rotating detainer disc cylinder provides superior master-keying possibilities with vast number of combinations. It offers optimum resistance against physical attack and picking. ABLOY CY411N, D Double Cylinder Tubular DeadboltBolt operated by key outside and inside. ABLOY CY412N, D Single Cylinder Tubular Deadbolt with ThumbturnBolt operated by key outside and thumbturn inside. ABLOY CY413N, D Single Cylinder Tubular Deadbolt with Key Lockable ThumbturnBolt operated by key outside and thumbturn inside.