Type: IP-PBX (500 IP Users) Maximum Ports: 240 TDM Users Built-in Hardware: PSU, CPU, Mother Board Universal Slots: 12 Built-in Ports: AIP, AOP, DIP, DOP, RS232C & Ethernet. Key Features 15-Party Conference 16-Port Voice Mail ISDN BRI/PRI GSM Gateway VoIP (SIP) Gateway Peer-Peer Calling Least Cost Routing Hotel Features PMS Interface Q-Sig SMPS or DC Power Supply Up to 8 T1/E1/PRIs Video Conferencing Web based Programming Tool