A respiratory mask with an inner mask for covering the mouth and nose. The inner mask includes an inhalation valve, an exhalation valve and a voice aperture. A microphone mount is removably attached above the voice aperture. Two microphones are attached with one oriented toward the mouth and the other...http://www.google.fr/patents/US5572990?utm_source=gb-gplus-shareBrevet US5572990 - Respiratory mask and microphone mount for use therein
Respiratory mask and microphone mount for use therein
