Replacement filter for the Oneisall fountain. You can be confident that the water your pet drinks is always clean, fresh and safe for their health. The Oneisall fountain filter consists of three layers that effectively remove odours, food residues, dander, heavy metals and other impurities. So you don't have to worry about the condition of your pet. Before using the product, you should immerse it in water for two minutes. To ensure high filter performance, you should change the filter regularly - at least once every 4 weeks. Manufacturer: Oneisall, Model: PWF-001, Compatibility: Oneisall Pet Fountain.