... , DTMF, FSK Adjustable line gain PCI/PCI-E analog card for Freeswitch and Asterisksupport 4 to 16 FXS/FXO ports Applications ... On Demand5, Voice Mail Services6, Call Centers7, Prepaid Calling Card System8, Callback Service9, Traditional Calls/VoIP Calls Conference Hardware and ... W*H): 140*104*12MM6, Weight: 152g The environmental instructions for using: 1, Temperature Operation: 0 to 80°C2, Temperature ...