Fanvil IP Video Door i31S is using standard IP/RTP/RTSP protocol for voice transmission. It combines all the advantages of the full range of compatibility. i31S has a variety of enterprise-level features and is compatible with lots of major platforms, such as 3CX,

Fanvil IP Video Door i31S Feature List 

• The system design adapts to operating under various environmental conditions and

temperatures (supports temperatures ranging from -40 to +70 Celsius.)

• Status indication icon

• All-in-One(Access Control, Intercom, and Broadcasting)

• Access Control(DTMF, Password, RFID/IC, Indoor Switch)

• Built-in 3W speaker and AEC, support high-quality hand-free communication.