The M3904 phone supports up to 12 lines and has a five-line by 24 character display; the largest in its class.
The Nortel M3904 includes a personal directory PC facility, which allows a directory of up to 100 contacts to be created on a PC and then downloaded straight to the telephone. An Accessory Connection Module (ACM) can be attached to the M3904 phone, allowing it to support up to two ‘snap-in’ cartridges.
In addition, full duplex, hands free mode can be achieved through the Full Duplex Hands Free accessory that snaps in to the ACM
