Buy from Amazon : br br Grandstream GXP2100 Mainstream 4-Line IP Business Phone br br Expandable secure and easy to manage br 4 dual-color line keys with 4 SIP accounts 3 XML programmable context-sensitive soft keys up to 5-way conference and up to 11 call appearances with 7 dual-color BLF extension keys br HD wideband audio superb full-duplex hands-free speakerphone with advanced acoustic echo cancellation and excellent double-talk performance br Automated phone book synchronization with directory server using XML br Integrated real-time web applications weather stock currency RSS news etc