Oatey 39220 Sure Vent Air Admittance Valve

Air admittance valve For use as a secondary vent Opens and closes as needed by building’s plumbing system Use as an air inlet source One size approved to handle up to 4-Inch vent pipe Complies to ASSE Standard 1050 and 1051. For use as a secondary vent. One size approved to handle up to 4″” vent pipe. Opens/closes as needed by building’s plumbing system.