Our builder provided a standard lock with keys for the main entrance. We tend to often use the entrance through the garage and one day while at work, the wife managed to lock herself out. She ended up walking 2 miles to pick up our spare keys and I didn't want that to happen again. So, I bought the Kwikset - Smartcode 913 and installation as well as reprogramming the deadbolt to use our existing keys was a breeze. I've had this deadbolt for about 6 months now and can't be happier. I love that it automatically locks itself in 30 seconds and the ability to set codes for visitors. Overall, it is a great buy and I would highly recommend it to anyone in the market for a similar product.