Lightinthebox 905a Biometric Fingerprint Door Lock with Key & Ic Sensor Open optical fingerprint sensor, touch on electricity.The two touch buttons on the rear panel, set the button and delete button. Fingerprint door: 100 (including management fingerprint), of which the first three for the management of fingerprints. Normally open / close mode converter design flexible, easier to use. Handle and lock cylinder can be freely interchangeable, easy to install. 2 Years free warranty from Lightinthebox!!!!