The audio door telephone controller device is connected to the telephone extension at the door. When the door needs to be opened, the visitor dials the telephone in the room on the door operator. After confirming the identity of the visitor through the telephone, the internal staff can enter the password on the telephone to open the door remotely.

Audio door telephone When a visitor arrives, whether the resident is at home, in the office or on business trip, the door can be opened by remote control through the telephone or mobile phone. The audio door telephone device is the product upgrade of the traditional intercom access control system. It does not need wiring and is easy to install and maintain. It can use both local telephone lines and internal extension lines.