Vernatone corrosion-resistant fiberglass muffler for use above the waterline. Vernatone Round Muffler 2 1/2 in. Inlet/Outlet | Centek Industries 1000103 Vernatone Round Muffler 2.5 in. Inlet/Outlet/li> Corrosion-resistant e-glass construction Accepts 2.5 in. inside diameter exhaust hose Length 21.62 in. Diameter 5.58 For gasoline and diesel inboard applications For above waterline use only