This is our Machinery Keyless Keypad Security Entry Door Lock with Emergency Override Keys. It is Suitable for office use, home or apartment. Caution:Please read the instruction thoroughly before using the unit. Please retain this manual for future reference. Great for office use, home or apartment Zinc alloy integrative structure Easy to installation Opened by code Suitable for Both left door or right door Standard 2 3/8" backset Size of the keypad part: Length:108mm4.25in Width:43mm(1.73in) Thickness:21mm(0.83in) Size of the back part: Length:108mm4.25in Width:43mm(1.73in) Thickness:17mm(0.67in) Material: Zinc alloy Color: Silver Package including: 1x Door lock 1x Instructions Note:Light shooting 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 +/- 1-3 cm.