01 . Passage function: You can use the code to set the lock in passage mode 02. Up to 9 digits can be used in a code - the code can be edited with any of the digits from 0 to 9. 03. Under-voltage indication: It can automatically inform the user to replace batteries. 04. Emergency unlocking: The lock can be opened by a mechanical key. 05. Code protection: It alarms for 1minute after three unsuccessful attempts using an incorrect code, during alarming time, all keys are disabled automatically.