Designed for light telephone use in areas such as manufacturing, warehouses, and other business environments, the M3902 brings the display-based interface and handsfree capability to this basic, single-line phone. Enhancements such as self-labeling keys, Smart Mute, and a host of user-selectable options make this a powerful single-line solution. The M3902 also increases its capabilities by supporting a cartridge accessory that conveniently snaps into the back of the phone.