Suit for the T27P and T29GWM, WMB-T27/9 Series.

Audio Features
•HD voice: HD handset, HD speaker
•Codecs: G.722, G.711(A/µ), G.723, G.729AB, G.726, iLBC
•DTMF: In-band, Out-of-band(RFC 2833) and SIP INFO