> 4-way opening: Bluetooth, Mifare Card, password and mechanical key
> Voice prompt: All settings can be finished by following voice prompt
> Privacy password: xxx+password+xxx, preventing password to be seen by others
> Passage Mode and Non-disturbance Mode optional
> Auto lock when come across a consecutive invalid passwords or cards
> Low Voltage alarm(<4.5V), doorbell
> Huge storage: 50 cards, 50 passwords
> Emergency power supply outside
> Three colors optional
> Zinc alloy material