Pentair #2-442 N674 70 Duro Valve Flange O-Ring

The Pentair #2-442 N674 70 Duro Valve Flange O-Ring (part number 273512) is a precision-engineered sealing component manufactured for use with large-scale Pentair commercial and residential multiport control valves, slide valves, and high-capacity filtration systems. Molded from premium nitrile (Buna-N) rubber with a specialized 70-durometer hardness rating, this heavy-duty gasket provides the ideal balance of elasticity and mechanical resistance required to handle tight compression fittings. Its primary structural role is to sit inside the machined perimeter channel of the 3-inch or 4-inch plumbing flange adapter, creating an absolute airtight and watertight seal at the critical junction where the valve body attaches to the filter tank. Engineered to withstand continuous high-velocity hydraulic flow rates, intense system pressures up to 50 PSI, and relentless exposure to corrosive pool sanitizers like chlorine, bromine, and acid washes, this robust O-ring actively prevents dangerous external bypass leaks. Because it is a streamlined rubber component with a thick cross-sectional profile and wide diameter, this individual sealing ring carries a net product and shipping weight of approximately 0.12 pounds (about 1.92 ounces).