FXO Card with 4 FXO Ports,Low Profile For 2U,Analog FXO Voice Card Supports Elastix FreePbx PCI Connector Quad Span Analog Card PCI Connector Supports Freepbx,Issabel,Asterisk, ... with Low Profile for 2U server Asterisk Card with 4 FXO modules Using the card, open source software and PC,you can build a telephone solution / IP PBX / call center /SIP server/VoIP Gateway Trunk appliance based on the card easily at a very low cost.