... and Asterisksupport 4 to 16 FXS/FXO ports Applications: 1, PBX/IVR Services2, VoIP Services3, VoIP Gateways4, FAX Server, FAX On Demand5 ... using: 1, Temperature Operation: 0 to 80°C2, Temperature Storage: -35°C to 120°C3, Humidity: 10% to 90% Non-condensing4, Voltage: 5V ...