Yeastar S20 VoIP PBX

4-Port IP-PBX Support 20 users and 10 Concurrent Calls LAN: 1 × 10/100 Mbps WAN: 1 × 10/100 Mbps Voicemail: 5000 min (expandable) VoIP Trucks: 20 Protocol: SIP (RFC3261), IAX2 External Storage: TF Card Built-in call recording capability Includes: (2) Telephony Line Cord (1) Power Adapter (1) Network Cable (4) Rubber Feet (1) Warranty Card (1) Quick Start Guide