GXP2170 VoIP SIP telephone, 2 x Gigabit Ethernet, 12 x line keys, AC + PoE, 4.3 inch colour TFT LCD, HD audio, RJ9 headset jack, EHS support for specific Jabra, Plantronics and VBeT headsets (EHS cable required), Bluetooth V2.1, 1 x USB, add up to 4 expansion modules (sidecar / attendant console)