The T-Cone Plug is the industry leader in reusable duct plugs. Containing no metal parts, the T-Cone provides a reliable seal against infiltration of debris, water or sewer gases. In blowout tests, the T-Cone Plug has also been able to withstand 20 feet of head pressure. The T-Cone’s two-piece, threaded design, consisting of an expandable sealing gasket with a tapered polyolefin-mating plug, provides for easy installation and removal.