The grandstream gxp2170 IP phone Linux-based model features 12 line keys with up to 6 SIP accounts, 5 xml programmable soft-keys, 48 digitally programmable blf/fast-dial keys with dual color LED, and the ability to use the gxp2200ext extension module for up to 160 additional blf/fast-dial keys. The gxp2170 also features a vivid 4.3″ 480X272 color LCD, 5-way conferencing, HD wideband audio, full-duplex speakerphone with advanced acoustic echo cancellation, dual gigabit network ports, integrated, bluetooth, USB and ehs.