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 nylon mesh. The water is deeply purified and safer Features: Pack and Size: Value pack of 4 filters. Compatible with PingPin water fountain. Size: Diameter: 9.9cm/3.9in; thickness: 8mm/0.31in. Dual-Action Filters: Resin and active carbon. Resin can soften water and reduce the chance of lithiasis. Activated carbon can adsorb impurities and odor, keep the water fresh and clean. 3-Layer Filtering: Water quality can be improved by the 3 types of filtration. The external nylon layer on each filter captures hair and debris. Three steps of filtration can assure the quality of the water and enhance the taste of fresh water for your cats. Easy to Use: Rinse the filter with water thoroughly before using, easy to mount it on