Double Cylinder Captive Deadbolt Lock
This lock is best suited for doors that have panes of glass on or around the door. It combines a single and double cylinder deadbolts best features and gives you this intuitive Captive Double Cylinder Commercial Deadbolt Lock.

How Does It Work?
This captive double cylinder lock uses a cylindar on both the inside and the outside of the door you install it on. When someone wasnt to lock the door from inside, a captive thumbturn ket is inserted into the (inside) cylinder and the bolt is then locked, at which point the key is held captive and cannot be removed from the inside of the cylinder. This is to protect the "key" and to make sure it is readily available to unlock the door at a moments notice in case of an emergency. In order to release the captive key, the door has to be first unlocked, then a second key must be inserted into the outside cylinder and turned 90 degree. This will enable to key to be released, and cause the lock to act like a double cylinder deadbolt.

This product is well suited for homes who have small children or an unoccupied buildings.

Caution: the double cylinder function should only be used when the building is unoccupied. Always check local building codes.

Notes: Both the BiLevel and High Security locks have the same key registration requirements to protect against inauthorized key duplication. The High Security locks have more internal anti-attack features than the BiLevel licks. Both function alike and look almost identical. Both have the same warranty.The High Security locks and cylinders are recommended on all exterior doors.