mechanical keyless code door lock

a. No need of energy and key,only input the code to unlock the door.
b. Full mechanical designd,also has the function of electronic product.
c. Has 12 keys,the secret code can be selected from 1 digit to 12 digits freely.
d. Very easy to change the code,you can change the code without pulling down the lock from the door with a small tool,under the condition that you know the previous code.
if the code is forgotten,a spare key can be used to unlock the door then the code can be reset. It can set into three working conditions:using the code,nonuse the code,inside securd.
suitable for the suite,villa,office building ect.