Pentair PXC Small Lid Replacement for Pool Filter 100 Sq Ft

The Pentair PXC Small Lid Replacement for Pool Filter 100 Sq Ft (part number R172540 or R172540Z) is a rugged structural enclosure component engineered specifically for the top dome section of the compact 100-square-foot Pentair PXC-100 cartridge filtration system. Injection-molded from a high-impact, fiberglass-reinforced polymer composite, this thick-walled pressure vessel cap serves as the primary sealing dome for the filter core. Its primary functional role is to lock tightly over the lower tank body and its main sealing O-ring via a heavy-duty locking ring assembly, establishing an absolute airtight and watertight containment boundary that enables the system to safely withstand continuous hydraulic flow velocities and operating pressures up to 50 PSI without expanding or leaking. The lid architecture includes integrated, molded internal thread ports designed to securely hold the manual air relief valve assembly and pressure gauge at its highest point for efficient air pocket purging. Engineered to survive continuous outdoor UV weathering, intense summer heat, and prolonged exposure to concentrated pool sanitizers like chlorine and bromine, this robust lid prevents structural warping and catastrophic pressure failure. Due to its thick-walled, heavily reinforced composite dome architecture, this individual small lid assembly carries a net product and shipping weight of approximately 5.50 to 6.20 pounds.