A heat and moisture exchanger (HME) media disk and associated virus and bacteria filter disk are placed in a housing of two clear plastic shells ultrasonically welded together and having ports at opposite ends of the housing for connection of flexible respiratory tubing to them. A guide vane is situated...http://www.google.es/patents/US5590644?utm_source=gb-gplus-sharePatente US5590644 - Heat and moisture exchanger for breathing
