Pentair Bulkhead Retaining Nut

The Pentair Bulkhead Retaining Nut (part number 192115Z or 190143, depending on the specific filter line) is a heavy-duty mechanical fastener engineered for various Pentair cartridge, D.E., and sand filtration systems, including the Clean & Clear Plus, FNS Plus, and Quad D.E. series. Injection-molded from a dense, glass-reinforced thermoplastic composite, this thick-walled nut features robust internal threads designed to spin onto the external bulkhead fittings protruding through the lower filter tank shell. Its primary structural role is to clamp the plumbing bulkhead securely against the tank wall, sandwiching the internal seals to form an absolute watertight and airtight compression boundary that can withstand high-velocity hydraulic flow and intense operating pressures up to 50 PSI. Built to resist stripping, cracking, and chemical degradation from continuous exposure to chlorinated pool water, acid washes, and fluctuating temperatures, this locking nut ensures the integrity of the main inlet and outlet plumbing connections. Despite its rigid, high-torque construction, this compact hardware component is lightweight, carrying an individual product and shipping weight of approximately 0.15 pounds (about 2.4 ounces).