1、4 in 1: Keyless entry smart lock, with 4 ways to unlock, such as fingerprint, password, mechanical keys and for TTLOCK app, high securitity, anti peeping, more convenient for using. 2、Fingerprint Unlock: Smart fingerprint lock can identify fingerprints within 1.5 seconds and store up to 50 fingerprints, the error recognition rate is low, the recognition speed is fast. 3、Low Battery Reminder: Smart lock with low power consumption, requires 4 AAA batteries(not included), low battery reminder, equipped with USB interface for emergency charging. 4、Bluetooth APP Control: Support for Android 4.3, for IOS 7.0 and above, bluetooth door knob supports for TTLOCK app, remote control your door, share temporary passwords and dynamic passwords. 5、Easy Installation: Fingerprint door lock is designed to fit door thicknesses from 35‑65mm/1.38‑2.56in. No wiring and no drilling. Fit both left handed and right handed doors.