I've had this deadbolt on my front door for almost 3 years now. It even stood up to the front door being kicked in by a burglar and was able to reinstall it on the new door. Uses 4 AA batteries that last several months before needing to be changed. Touchpad will alert you when batteries are getting low. Can program up to different codes. Has stood up to the outdoor elements and still looks brand new. Very satisfied with this purchase.