Grade 1 security double deadbolt with Smart Key cylinder. Smart Key cylinder eliminates traditional pins and springs. Cylinder design provides instant re-key functionality. Smart Key cylinder is a bump-resistant, higher pick-resistant lock. Included with each lock is the re-keying learning tool that allows the lock to be re-keyed in 3 easy steps. Fits all standard doors 1-3/4″. Standard adjustable backset 2-3/8″ – 2-3/4″. Requires 2-1/8″ diameter crossbore hole and 1″ diameter edge bore.