Product Detail 4 Ports for connecting analog telephones or POTS lines Half-length Analog Card Up to 4 FXS or FXO Modules High Performance Echo Cancellation (HPEC) Software (Optional) AEX410 for use with a PCI-Expressx1 compliant slot - Bundled with VPMADT032 as AEX410PE . The "Digium AEX410P Base Card PCI-Express x1 Supports up to 4 Single FXO/FXS Ports" is best product for you. We recommended Digium AEX410P Base Card PCI-Express x1 Supports up to 4 Single FXO/FXS Ports