【Compatibility】: This replacement filters are ONLY compatible with 230oz 1.8GAL 7L Dog Water Fountain with 5 Layer Filter; 【Four Layers Of Filtration Ensure That Every Drop Of Water Is Fresh】: Activated carbon eliminates bad odors; non-woven fabric captures cat hair and impurities; and sponge filters debris to prevent clogging and damage to pump. Maximum protection for your pet's healthy drinking water; 【12 Pack Water Fountain Filter Replacement】: Included 12 packs of replacement filters, 12 packs of replacement pre-filter sponge and 12 mesh-filters. Multi-effective filtration ensures that pets drink fresh water; 【How to Use】: Please soak the filter in water for 5 minutes before use and rinse thoroughly under running water; 【Frequency Of Replacement】:Replace the cat water dispenser filter once in 4 weeks in summer and once in 4-6 weeks in winter to ensure clean drinking water. More frequent changes if more than one pet is using the water fountain; 12 Pack Cat Water Fountain Filter Replacement for 5 Layers Filtration System 230oz/7L Pet Water Fountains, Activated Carbon Dog Fountain Filter Replacement with Sponge&Bag for 1.8GAL Dog Water Bowl