Pentair Union Nut C Clip

The Pentair Union Nut C-Clip (Product #: 271091Z / 271091) is a factory-original OEM replacement retaining ring engineered to provide a secure mechanical lock within plumbing union assemblies on premium pool and spa filtration systems. Utilizing a specialized split-ring "C" design, this heavy-duty snap clip snaps firmly into an integrated perimeter groove on the exterior of standard 1.5-inch or 2-inch bulkhead adapter tailpieces, acting as a structural backstop that prevents the loose-spinning union nut from sliding off the pipe. This critical alignment interface is widely used to connect Pentair Hi-Flow™ side-mount and top-mount multiport backwash valves to Triton® II sand filters, Quad D.E.® separation tanks, and high-performance circulation pumps. Injection-molded from a premium, high-density engineering polymer, the component provides exceptional structural flexibility to bend without snapping during installation, total immunity to aggressive pool chemicals or salt-chlorine generation, and built-in UV stabilizers to prevent embrittlement from continuous outdoor weathering. By absorbing the constant hydraulic vibrations, line pressure surges, and backpressure generated by the pool system up to a maximum continuous baseline of 50 PSI, this retaining clip ensures the union assembly compresses its internal o-rings uniformly, preventing costly pressure-side water weeping or suction-side air induction. The physical dry weight of this single Pentair Union Nut C-Clip is exceptionally light at approximately 0.02 pounds (roughly 0.32 ounces, with a packaged shipping weight of approximately 0.05 pounds), providing pool professionals and residential managers with an indispensable, highly resilient, and featherweight hardware component for flawless water circulation networks.