HYDRATION - The duo-density polyester pad removes any unpleasant odours or tastes from your Pets Water making it FresherEXTEND FOUNTAIN LIFE The Drinkwell Replacement Filter Cartridges will prevent Food, Hair and other Large Debris from being circulated through the Fountain, making cleaning easierIMPROVE WELLBEING- Keeping your Pet hydrated is one of the best ways to improve their health, for Cats and Dogs with kidney disease or cystitis Drinking Clean, Fresh Water has many benefitsLONGER LASTING - Lasting weeks at a time the Charcoal Filters are an affordable, consistent way of improving the Quality of your Cat or Dogs Drinking WaterCOMPATIBILITY The Drinkwell Replacement Charcoal Filters are compatible with the PetSafe Original, Platinum, Mini and Big Dog fountains.