ESI 5000-0425 Communications Server CS-A12 PC 12 Analog Station Card (Refurbished)Key Features: Connects up to 12 analog devices (only), such as fax machines and cordless phones This card uses 12 station ports and no CO ports Each port provides a standard 24 volt, two wire phone connection. Only one analog device can be connected to each port Compatible with: ESI Communication Server 200 ESI Communication Server 600 ESI Communication Server 1000