AT&T 1040 4-Line Basic Expandable Corded Telephone AT&T 4-Line Basic Expandable Corded Telephone system features a useful speaker phone, 32-number speed-dial, 16 intercom station, 3-way conferencing, And can be networked into a system of up to 16 phones. It is simple to set up and use. In addition to its key functions, this phone also offers paging, intercom, 4 illuminated line signs, and call transfers between station, 2 data slots, Centrex interface, power failing security, and much more Compatible with the ATT1070 and ATT1080 (not backwards compatible with other AT&T 4-line models) Speakerphone 1 to 4 line capability Intercom between stations Expandable up to 16 stations Call transfer between stations 32# Speed dial 16 Intercom number locations (can be used for one-touch memory, two-touch memory, and direct station dialing) 2 Data ports Easy to install 3 Party conferencing (inside or outside lines, or a combination) Power failure protection for all 4 lines (battery not included) Individual station paging (intercom) or system-wide paging Headset jack (2.5mm) 4-Line backlit LCD display Redial / hold / mute / flash Last 6 number redial Volume control for receiver, speakerphone, headset, ringer Do not disturb Wall mountable (bracket included) Auto line selection Display dial Rapid scroll navigation pad New message indication 4 Lighted line indicators Auto redial Memory loss protection Selectable ringer tones Hearing aid compatible DSL Compatible (splitters/filter not included) Every unit in the system must be assigned an extension number for the intercom feature to work 1 Year manufacturer's warranty Dark silver