PERFECT MATCH: Fountain Filter compatible with most Pet Fountain and with other flower fountain of same size.Size is around 13*13*8.5 cm / 5.1*5.1*3.4 in,Pack of 8 filters. KEEP YOUR PET HEALTHY: Every filter for cat fountain is composed of a cotton layer, activated carbon, and an ion exchange resin. It can effectively remove impurities, filter hairchlorine, heavy metals, and odors. Get high-quality drinking waterhelps to increase water consumption and reduce the risk of urinary tract infectionsmake pets live longer and healthier. FREQUENCY OF REPLACEMENT: We suggest to replace the pet fountain filter 2-4 weeks to keep the water fresh and clean NOTE: To help prevent the charcoal dust from shedding, please rinse the replacement filters for cat fountain/dog water dispenser with water thoroughly before use, providing the clean water for cats and dogs.