Wideband Audio : Support for wideband (G.722 codec, adherence to TIA 920), including handset, headset, and speakerphone. Voice lines : 6x Telephone Lines Navigation Buttons : 4x interactive soft keys Codec Support : G.711a, G.711, G.729a, G.729ab, G.722, and iLBC audio compression codecs are supported. Graphical Display : 5-inch (12.5 cm), high-resolution (320 x 222), graphical monochrome 4-bit grayscale display. Speakerphone : Full-duplex speakerphone with acoustic echo cancellation. Colour : Charcoal QOS : Supports differentiated services code point (DSCP) and 802.1Qp standards.