Compatible with Catit PIXI Water Fountain 2.5L These filters are designed to fit the Catit PIXI Water Fountain (2.5L/84.5 fl oz). Please note, these filters are not manufactured or sold by Catit. Easy to Use for Optimal Performance Before use, simply soak the filter in water for 5 minutes, then rinse it with running water to remove excess carbon dust. For best results, replace the filter every 2-4 weeks, depending on the number of cats using the fountain. Clean and Fresh Water for Your Cat Each filter is constructed with cotton, activated carbon, and ion exchange resin to effectively remove hair, heavy metals, and other impurities, enhancing the taste and quality of your cat's water. Promote Health and Hydration Providing your cat with clean, fresh water helps encourage better hydration, reducing the risk of urinary tract infections and supporting overall health. Ensure your cat stays hydrated and healthy with each sip!