1、The unique design with sensitive button input and built-in 50 sets of passwords (the length of the password is 4-8 digits), is versatile, practical, and universal for most people, not limited to the user's age. Its performance and security has greatly exceeded the mechanical lock. 2、60-70mm/36-76in adjustable locking tongue, more convenient and simple to use and install.  3、Users can change passwords frequently to prevent passwords from being stolen.  4、Has anti-monitoring function, this dummy password is helpful to prevent from being watched, just enter a few digits in front of the correct password as a dummy password. 5、With low battery reminder function, the buzzer alarms and red light flashes for 5 seconds when the voltage is lower than 8V, which will remind you of replacing battery. 6、Adopts low-decibel process design, to avoid disturbing family at night effectively. 7、4pcs AA alkaline battery, with ultra-low power consumption and long service life for one year. 8、Equipped with keys for emergency, you can store it in a concealed place of the car, convenient for you to use. 9、The door is automatically locked after 3 seconds, to prevent theft from stealing something. 10、 After entering the wrong password for 3 consecutive times, the lock will alarm and light will be red, locking the keyboard for about 3 minutes. 1 x Front Lock Plate1 x Rear Lock Plate1 x Lock Tongue2 x Mechanical Key1 x Lock Catch2 x Pack of Screw 1 x Instruction Manual Item Type: Door lockColor: Silver, black(optional)User Capacity: Built-In 50 sets of passwordsPassword Length: 4-8 digitsNumber of Pressing Password: 100,000 timesBattery Life of the Product: 365 daysDoor Opening Method: Password, spare mechanical keyDoor Opening Direction: Regardless of the left and right directionPower Supply: 4 AA alkaline batteries (6V) (not included)Low Battery Reminder: 4.8V low voltage alarm promptStandby Current: 15μA-30μA Working Current: 200mAWorking Temperature: -15 - 50 °C Working Humidity(RH): (45-85)%Material: Zinc alloy front panel, plastic rear panelLock Tongue Material: Stainless steelSize of Lock Tongue: Approx. 60-70mm/ 2.36- 2.76in(adjustable)Applicable Door Thickness: Approx.35-55mm/ 1.38- 2.17inFront Lock Plate Size: Approx.61x 140.2mm/ 2.4x 5.5inRear Lock Plate Size: Approx. 71.8x 162.2mm/ 2.8x 6.4inThickness of Front Lock Plate: Approx. 29.3mm/ 1.2inThickness of Rear Lock Plate: Approx. 52.3mm/ 2.1in