Emtek Assa Abloy | Single Cylinder Deadbolt Square - Flat Black 2-3/8" and 2-3/4" Backset Schlage C Keyway Standard Door Prep Solid Forged Brass Keying: Single Cylinder Deadbolt - Keyed Different - 8469 KD - When keyed different the locks will have different keys. Each lock has its own unique key and can not be opened by the other keys from the same locks. Deadbolts are locked/unlocked from inside by thumb turn or outside by key. Normally used on exterior doors. Single Cylinder Deadbolt - Keyed Alike - 8469 KA - When keyed alike, all locks in a set can be opened with the same key. Deadbolts are locked/unlocked from inside by thumb turn or outside by key. Normally used on exterior doors. Model: 8469US19