Offering wireless audio access control system: * Features: - Wireless audio access control system - Wireless Doorphone GP-MA600 has the functions of wireless intercom and remotely opening door. - It overcomes the limitation of the wireless doorbell and access control system which can not talk, can not open door remotely, and avoids the trouble of run cables indoor. - It has an update substitutes for the traditional doorbell and access control system. It is suitable used in office, house, villa, or tier building.* Product Features: 1. Full duplex audio between Call Station, Base and Handset. 2. Communication range is more than 300 meters in free range space. 3. Easy installation. Run cables indoor is not necessary. 4. System is fully expandable up to maximum of 4 Handsets. 5. Callers are transferable between Handsets. 6. Handsets can remotely open automated gates or electric locks.