Description: Extension of a full-duplex speakerphone Exclusive pre-set equalizer for adjustable audio tone and sound quality 100 name / number Call Waiting Caller ID (CID) 16 programmable shortcut keys Support for 2-line with dedicated buttons displayed on the status bar, 2-line programmable voicemail indicator Button Easy installation 3 conference participants, "Do Not Disturb (DND) with a blue backlit LCD Headset jack and button user switching data ports compatible with hearing aids, digital volume control