Kwikset 159SQT-S Halifax Double Cylinder Deadbolt with Smartkey Technology, Iron Black,Matte Black, 4.7 x 4.1 x 3 inches

Double Cylinder Function: The deadbolt is thrown and retracted by a key from either side. As you will not be able to unlock this from the inside without a key, please check your local fire code to ensure this is allowed before purchasing. SmartKey®: This technology allows you to re-key your lock in seconds with 3 simple steps and features stainless steel racks, pins, and side locking bar for increased strength and security.