The Bestway Filter Cartridge Type VII, Type D is a replacement swimming pool filter cartridge for your Bestway Flowclear 530 gallons/hour Filter Pump. This filter cartridge sifts out the debris and dirt in your above ground swimming pool so the pump can refill it with clean pool water. It's recommended you replace your filter cartridge every 2 weeks to ensure your pool obtains the highest standard of cleanliness and hygiene. When you maintain your pool's filter, the water in your pool stays attractive and fresh all summer long, which makes it all the more enjoyable for your family and friends. For your Bestway pump's best performance yet, get the Bestway Filter Cartridge Type VII, Type D.