[ TO UNLOCK]: Advanced Keyless Entry Smart Door Lock: Fingerprint + Anti-peep virtual password + Physical Key, fingerprint recognition rate up to 98% and open the door just need 1 second. You can add 50 groups fingerprints, the trouble of forgetting to bring the key when you go out. [DIY INSTALLATION]: Keyless Entry Door Lock is designed to fit US standard door, Backset 2-3/8 inch(60mm) and 2-1/8 inch(70mm), door thicknesses from 1-3/8 inch to 2-1/8 inch(35mm -55mm). No wiring and no drilling. Fit both left handed and right handed doors. [Boarding & HOMEOWNER]Fingerprint door lock providing your room with an added level of safety, it is simplistic design for office, apartment or other private spaces. [EMERGENCY CHARGING]: Smart door lock requires 4 AAA batteries (not included), According to the frequency of use, it can be used for up to 12 months. It has low battery reminder function, equipped with a USB interface for emergency charging. size:15x6.5cm Material:Zinc alloy colour:black Package Contents: 4 set x door locks(Without battery) 8 x keys 4 set x installation accessories 4 x Chinese English manual Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.