The Yealink T54W is a Linux based mid-level IP phone with a 4.3' pixel color display that is fully adjustable. The T54W supports 10 line keys and 16 SIP accounts and features built-in Bluetooth and Wi-Fi. The T5 series features Yealink's Acoustic Shield technology for distraction-free voice clarity. The technology uses multiple microphones to create a virtual shield between the speaker and the person on the other line. When enabled, it blocks out or mutes sounds that are considered to be outside the shield so that the person on the other end hears the speaker clearly New structure design USB 2.0 port for USB recording and wired/wireless USB headsets HD Voice with Yealink Acoustic Shield technology Dual-port Gigabit Ethernet PoE support