The Posi-ClearCartridge Filter gives you everything you could ask for in a filter. It delivers top-of-the-line cartridge performance to keep pools sparkling clear, trapping particles as small as 20 microns (an average grain of sand is 1,000 microns). The new side entry design optimizes flow for nearly 50 percent greater efficiency than any other single cartridge filter on the market, earning it the Pentair® Eco Select® Brand for our most environmentally responsible equipment choices. Cleaning is a breeze - just open the top, remove the cartridge, and hose it off. And, its durable fiberglass tank ensures exceptionally long life. The Posi-Clear RP is the ultimate in convenience, and delivers refreshingly clear pool water.