Elevate your filtration game with our pool filter balls, crafted from 100% blue polyester fiber. Our balls bring superior filtration performance, are compatible with various filter systems like sand filters, cartridge filters, and DE filters. Enjoy swimming in crystal clear water in no time! | Vevor | | Pool Filter Balls for Sand Filter, 3.1 lbs, Filter Balls Replace Pool Filter Sand, Reusable Polyester Fiber Filter | Blue | Best Buy