Compatible with most sand filter pool pumps Reusable sand replacement with only 0.06 lbs (28 g) of filtration balls needed to replace 2.2 lbs (1 kg) of sand Hand-wash only; mesh bag included for convenient cleaning Made of 100% recyclable and non-toxic material Lower pressure allows for higher flow rate and longer lifespan for pool and pump Lightweight & easy to transport Not compatible with or necessary for sand filter backwashing function Contents: 500 g (1.10 lbs) Polysphere filtration balls