Yealink SIP-T31. Product type: IP Phone, Product color: Gray, Handset type: Wired handset. Phonebook capacity: 1000 entries. Display: LCD, Display diagonal: 2.3", Display resolution: 132 x 64 pixels. Voice codecs: AGC, AJB, CNG, G.711Mu, G.711a, G.722, G.723.1, G.726, G.729, G.729A, OPUS, PLC, VAD, iLBC. Ethernet LAN interface type: Fast Ethernet, Ethernet LAN data rates: 10,100 Mbit/s, Networking standards: IEEE 802.1Q, IEEE 802.1p, IEEE 802.1x, IEEE 802.3af