Corded - 4 x Phone Line - Caller ID AT&T 1080 4-Line Expandable Corded Small Business Telephone with Digital Answering System - Corded - 4 x Phone Line - Caller ID Four-line, corded phone is expandable up to 16 extensions Offers 3-party conference calling, 200-number directory and selectable ring tones Features speakerphone, handset and volume control Includes six-number redial, rapid scroll, memory loss protection, two data ports and more Compatible with both hearing aids and headsets Four-line corded system phone is expandable up to 16 extensions and features a digital answering system with 60 minutes of record time, auto attendant, remote access, call screening/intercept, and time/day stamp. Offers two data ports, 200 name/number directory, 32 speed dial and 16 intercom number locations, three-party conferencing, call transfer, auto line selection, Do Not Disturb function, flash, volume control on handset, speakerphone and headset, hold, intercom, last six-number redial, memory loss protection, mute, page, power failure operation, rapid scroll and selectable ring tones. Trilingual setup menu can be viewed in English, French or Spanish. Hearing aid compatible. 2.5mm headset compatible. Compatible with AT&T 1070 and 1040. DSL compatible (splitter/filters not included).