{"product_id":"pentair-u9-359-black-drain-plug-o-ring","title":"Pentair U9-359 Black Drain Plug O-Ring","description":"\u003ch2 data-path-to-node=\"0\"\u003ePentair U9-359 Black Drain Plug O-Ring\u003c\/h2\u003e\n\u003cp data-path-to-node=\"1\"\u003eThe Pentair U9-359 Black Drain Plug O-Ring is a factory-original, OEM replacement sealing gasket engineered to provide an absolute, leak-proof hydraulic barrier for standard drain plugs across an array of premium Pentair equipment pads. Designed to fit the heavy-duty 1\/4-inch NPT threaded drain plugs of high-performance pool and spa filtration pumps—including the ultra-reliable Challenger® High Pressure and High Flow series, SuperFlo® and SuperFlo VS variable speed lines, and WhisperFlo® workhorses—this tiny but critical component plays a vital role in protecting equipment pad integrity. Molded from a high-grade, chemical-resistant nitrile rubber (Buna-N) compound, the o-ring delivers superior structural elasticity and resilient memory compression, allowing it to withstand prolonged contact with high chlorine or bromine concentrations, pool mineral scaling, and heavy ozone treatments without degrading. When the drain plug is hand-tightened into the pump or filter body, this specialized ring compresses uniformly against the sealing seat to block pressure-side water leaks and prevent catastrophic suction-side air induction, which would otherwise cause pump cavitation and loss of prime. Built to endure severe outdoor weathering, freeze-thaw cycles during offseason winterization, and intense pump motor temperatures, it serves as a lightweight yet incredibly durable shield for your circulation plumbing. The physical weight of this single, featherweight Pentair U9-359 Black O-Ring is approximately \u003cb data-path-to-node=\"1\" data-index-in-node=\"1517\"\u003e0.002 pounds\u003c\/b\u003e (less than 0.04 ounces, with a nominal shipping weight of 0.01 pounds), providing pool professionals and residential owners with an indispensable, low-cost maintenance part for flawless water management systems.\u003c\/p\u003e","brand":"Commercial Pool and Spa Supplies","offers":[{"title":"Default Title","offer_id":53165479166063,"sku":"U9-359Z","price":3.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0678\/3785\/3807\/files\/261050_img2__71302_88c95911-bb5c-46ad-83b4-88026b44deec.jpg?v=1779895322","url":"https:\/\/commercialpoolandspasupplies.com\/products\/pentair-u9-359-black-drain-plug-o-ring","provider":"Commercial Pool and Spa Supplies ","version":"1.0","type":"link"}