Pleatco PBW5PAIR Spa Pool Filter Cartridge fittingsother A properly selected replacement helps A properly selected replacement helps preserve the original hydraulic behavior of the pump instead of forcing the repair to rely on a substitute that only partly fits The CMP 3 port Hydroseal diverter valve is designed for compatible plumbing applications where a 2 inch unionized multi path valve is needed A Pleatco cartridge helps preserve intended fit and contributes to more dependable flow and debris capture in the supported application Filter cartridges are useful because they help protect pumps and downstream equipment while supporting clearer water during normal operation