The Yale YDF 40 is one of the fingerprint digital door locks for Yale. You can access through password pin code as well. After a successful code entry and the unit unlocks, it will automatically re-lock after 30 seconds. It can be an additional lock to be installed above your existing door lock. All our digital locks are authentic and from local distributors with standard warranty. Installation is free and done by our professional and experienced installer with many years of digital lock/gate installation experiences. If the digital lock does not fit your door/gate for any reasons, we will gladly offer you a full refund or no charge. Thus, for digital locks you can choose to pay by the $0 Payment till Work Completion option during checkout. This is to assure our customers that everything works before they pay. Customers are our first priority.