20 DFU (Drainage Fixture Unit) capacity. Complies to ASSE (American Society of Safety Engineers) Standard 1050 and 1051 for use a a secondary vent. One size approved to handle up to 3" vent pipe. Opens and closes as needed by building's plumbing system, 1-1/2 - 2".
|Country of Origin||USA|
|Connection Size||1-1/2 In. to 2 In.|
|Use on Diameter Branches||Up to 3 In.|