MRC:
Those unusual or unique characteristics or qualities of an item not covered in the other requirements and which are determined to be essential for identification.FEAT
Special Features:
Plugs directly into definity systems digital wall jack or can be plugged into definity voice port that supports the 6400, 7400, 8400 series phones; full-duplex audio conferencing; echo cancellation; noise reduction, automatic gain control, high fidelity speaker, integrated keypad with 16 character , hypercardioid microphones