The ProSet AAV valve is unique because it is fire-rated and has been tested as a firestop device as well as a plumbing air vent. It is used to vent plumbing fixture openings and also replaces firestop collars that are normally used to firestop the penetration. The heavy-duty PVC valve is approved for installation within a fire-rated wall cavity and will hold 20 lbs. hydrostatic test. It is available with a special 25 flame- and 50 smoke-rated resin for installation within return air plenums or high-rise construction. ProSet Systems.