T31W: ?? Built-in dual band 2.4G/5G Wi-Fi (802.11a/ b/g/n/ac) - Yealink HD Voice - 2.3? 132x64-pixel graphical LCD with backlight - Two-port 10/100M Ethernet Switch - PoE support - Up to 2 SIP accounts - Local 5-way conferencing - Support EHS Wireless Headset - Unified Firmware - Support YDMP/YMCS - Stand with 2 adjustable angles - Wall mountable - Handset with hall switch