The Nortel M3902 phone is a single-line basic phone with display-based interface and hands free capability. The Nortel M3902 telephone is designed for light telephone use with more feature requirements for the Nortel Option PBX platform - 11C, 51C, 61C, 81C. The M3902 works great in areas like manufacturing areas and warehouses. The M3902 phone introduces the display based interface and handsfree capability to a single line phone. Enhancements such as self labeling keys, "Smart" Mute and a host of user selectable options make this a powerful single line set. The M3902 Nortel Phone set also increases its capabilities by supporting a cartridge accessory that conveniently snaps into the back of the phone.