Pentair #2-216 Buna-N O-Ring

The Pentair #2-216 Buna-N O-Ring (Product #: 35505-1425 / 190130) is a factory-original OEM replacement sealing gasket engineered to establish an absolute, leak-proof hydraulic barrier across a variety of premium pool and spa equipment components. Commonly utilized to seal critical fluid junctions such as pump strainers, valve stems, and union adapters on Pentair IntelliFlo®, WhisperFlo®, and Sta-Rite® circulation lines, this specialized round-profile ring sits securely inside a precision-machined plumbing groove. When the mating hardware components are tightened down, the gasket compresses uniformly to establish a positive pressure-side water seal and block catastrophic suction-side air induction that would otherwise cause pump cavitation and a loss of system prime. Molded from a high-grade, chemical-resistant nitrile rubber (Buna-N) compound, the component delivers exceptional structural elasticity, superior ozone resistance, and long-term compression memory, allowing it to withstand continuous exposure to high chlorine or bromine concentrations, heavy pool mineral scaling, and chemical shock treatments without distorting or dry-rotting. Built to comfortably manage continuous system operating line pressures up to 50 PSI and handle extreme seasonal pump room heat, this featherweight part ensures the entire filtration loop operates at peak hydraulic efficiency. The physical weight of this single Pentair #2-216 O-Ring is approximately 0.005 pounds (less than 0.10 ounces, with a nominal inner diameter of 1-1/8 inches, a cross-section thickness of 1/8 inch, and a packaged shipping weight of roughly 0.02 pounds), providing pool professionals and DIY homeowners with an essential, low-cost, and highly reliable hardware safeguard for flawless water management.