Yealink SIP-T34W HD Voice in handset & speaker w/ smart noise filtering ,Wideband Codec: Opus, G.722 , 4-lines and 5 N-way conferencing , 2.4″ color LCD display with 320X240 resolution , Adjustable LCD backlight , 4 Line Keys w/ LED, 5 Feature Keys, 6 Navigation Keys, & Volume Control Keys , Built-in Wi-Fi