They can be actuated by key on one or both sides as well as by a lock mechanism which rotates to move the bolt. A deadbolt has three main components. A cylinder is the part of the lock that the key ...

Now, they don't need a spare key ... locks have options for retrofit (you get to keep your current lock and put smart lock tech over it) or replacement (you choose a shiny, brand-new deadbolt ...

or ease of the install, these Home Key-enabled smart locks can help enhance your home’s convenience and security. With Apple Home Key, managing your home’s door locks has never been easier.