Replacement filter for the Oneisall fountain. You can trust 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 eliminate odors, food residues, skin flakes, heavy metals, and other impurities. This way, you don't have to worry about your pet's condition! Before using the product, you should soak it in water for two minutes. To ensure high filtration performance, you should replace the filter regularly - at least once every 4 weeks. Manufacturer: Oneisall, Model: PWF-001, Compatibility: Oneisall pet fountain.