ZyXEL V300. Display: LCD. Voice codecs: G.711a/? - G.722 - G.723.1A - G.726 (16/24/32/40) - G.729a/b. Supported network protocols: TCP/IP/TFTP/HTTP. Dimensions (WxDxH): 165 x 91.5 x 208 mm, Weight: 465 g. Operating temperature range (T-T): 0 - 40 °C, Operating relative humidity range: 20 - 95 %, Storage relative humidity range: 20 - 95 %