INTER ROCK by iNAHO Electric lock, electronic lock, automatic lock. You can unlock it with a card, PIN, smartphone, etc. It uses batteries, so no construction is required. This is a smart key that can be retrofitted to your front door. I've used it for 2 years, and since I had a film on the touch panel, I don't think there are any major scratches or problems. Please purchase with the understanding that it is used. No claims, no returns.