Starting with an HD-Audio Quality handset, Full-Duplex Speakerphone, Headset Support and 12 Programmable Function Keys providing any combination of 12 Line, Extension or Call Appearances, this feature-rich TC-12 phone also includes ten predefined hard buttons giving you one-touch functional access to the Speakerphone, 3-person Conference Calling, Do Not Disturb, Mute, Hold, Transfer, Messages and more.   Additional function buttons are provided to enable you to review and select from a detailed list of voice mail messages, Call History and Missed Calls . This phone also includes a 2-port 10/100 Switch and POE.