Trusted by the trade as the best in the business, Clean-Seal® 2 offers the same reliable features as the original Clean-Seal® with the ability to test the DWV system with either air or water no longer fill a DWV system from the stack or use other complicated multi-piece products|Plug, fill and drain from same cleanout tee|Multi-lobe gasket allows sealing of all tees including cast iron|Hand tighten in place, no tools required|Rubber cap protects hose connection when not in use|Check valve allows removal of hose after filling system and keeps DWV water from back filling into potable lines