VTech UP406 Corded Extension Deskset for VTech UP416 ErisBusinessSystem Main Console, Silver/Black Cordless mobility that is expandable up to a total 16 handsets (1 UP416 console, 15 desk sets), 3-party conferencing, Intercom, Cordless handset speakerphone, Caller ID/call waiting. Music on hold, Access the phone book from console or desk set, Wall-mountable 10 selectable ringtones 4 lighted line status indicators