Additional Details ------------------------------ Product description: The SIP-T44W IP phone is a feature-rich business tool for excellent communications and extended functionality. Integrated with Hall Switch, T44W gives you a quieter operation and environment. It is a 12-line IP phone that comes with a 2.8-inch color display with backlight and the EXP43 support. United Yealink Optima HD Voice technology, the T44W awards you the superb audio quality and crystal-clear voice communications. The phone feels quicker and more responsive when performing call features. With the built-in Bluetooth 4.2 and the built-in dual band 2.4G/5G Wi-Fi, the SIP-T44W IP Phone ensures you to keep up with the modern wireless technology and take the first chance in the future wireless age. Moreover, the T44W puts dual USB ports in a phone that makes USB headset, USB recording come true and Yealink EXP43 expansion module, and you can use any two of them freely according to your needs. T44W offers the same elegant appearance as the T4 line, but with improvements for greater interoperability and better collaboration. T44W better builds the Yealink ecosystem and is compatible with more Yealink headsets, supporting intelligent channel switching* and using the phone to configure and upgrade headset.