The Kwikset SmartCode Electronic Tustin Lever is a single cylinder electronic lever which is operated from the outside by code entry or key override and from the inside by using a thumbturn. It features a reversible lever making it suitable for both left and right handed doors. With the SmartKey technology it allows you to quickly and easily reset your lock's cylinder to work with any KW1 Keyway key without having to remove the lock from the door. Perfect for garage/house doors, store rooms, home office or utility rooms. Up to 30 user codes can be set up for controlled access. Keypad can be disabled entirely for entry using key only for long periods of inaccessibility and an optional one-time access code can be setup for emergencies. The 9V battery will last up to three years, depending on lock usage. The SmartCode 917 residential electronic lever has been tested in three areas most important to homeowners like you: security, durability, and finish. It is BHMA certified AAA - the highest residential security rating available.