【Good Filtration】Our foam filter cartridge has a high-density mesh structure that filters a wide range of impurities from the pool, effectively removing leaves, grass, hair, slag, pine, insects and other floating matter. Dimensions: 20 x 10 cm. Center hole: about 4 cm. 【Durable】This foam filter is made of high-quality sponge, which is flexible, not easily deformed, environmentally friendly and can be reused after cleaning for a long service life. 【Cost Saving】Replacing filter cartridges is part of your daily pool maintenance, regularly replacing paper filter cartridges will lead to increased costs and waste. Washable and reusable foam filters are an ideal alternative to disposable paper filters. There is no need to replace filter sponges frequently. 【Widely Used】Our washable foam filters are suitable for type A and most swimming pool filters on the market. To keep swimming pools, aquariums, bathtubs and spas clean, we recommend replacing them every two weeks for better filtration and