Compatibler:The cat fountain filter is compatible with a variety of cat fountains, please check the list of product pictures to make sure it is compatible with your cat fountain to avoid wrong purchase, thank you. Value Packr:10 cat fountain replacement filters and 10 pre-filter sponges are included in the package.   Materialr:The filter is made of environmentally friendly materials, the filter’s cotton layer and activated carbon would keep the water quality of the water dispenser clean, so as to provide healthy and pure water and protect the pet’s drinking water health. Filtration Roler:The filter help with water purification and eliminating odors, while the filter sponges can filter pet hair, dust, food scraps and more. Noter:Before using, please soak and rinse the cat water fountain filter with clean water, we recommend replacing the filter every 2-4 weeks.  cat fountain filters