Dimensions: 10.8*7.3*4cm. Central hole: about 4cm. . High quality: Made of high quality PVC foam, with sufficient thickness, moderate density, soft, not easy to deform, environmentally friendly and durable. . Good filtering: The foam filter has a high-density mesh structure. It can filter a variety of impurities in the swimming pool and effectively remove floating debris such as leaves, grass, hair, dirt, pine and insects. . Reusable: Each spa foam filter can be used for about 2 months. The filter sponge can be cleaned once a week to keep the water clean and reduce bacteria in the pool. . Save a lot: The advantages of washability and reusability can reduce your costs, reduce waste and have a longer service life than paper filter elements. .