Advantage Replacement filter for cat fountain. Keep your cat's drinking water is fresh, clean and safe. Helping you to take care of your cat's health. Most of the filters in the market are made of activated carbon. But this filters are made of high quality activated carbon, resin and cotton mesh. The water is deeply purified and safer. Features High-quality and Durable Material The water fountain filter is made of good quality activated carbon and cotton material, durable and reusable. Healthy Helper The water fountain filter filters hair and residue, removes odors and soften water, which is easy to disassembly and cleaning. Fountain Accessory The filter is your pet fountains necessary accessory. Own it, and provide your loving pet a healthy environment. Size *4 grids are approx 12.5*12.5*3.5 cm *8 grids are approx 12.7*12.7*3.8 cm Notice * Kindly remind that the water fountain is not included in this price. * The charcoal filter should be changed every 1 to 2 weeks. * Tip: Please soak in water for five minutes before using.