Compatibility: The cat water fountain filters are compatible with for Smartoo 152oz or 4.5L wireless cat water fountain. Let pets always get the best drinking experience.Quadruple Filtration: The filter uses activated carbon, ion exchange resin, maifanstone and non-woven fabric to effectively odors, remove heavy metals, and soften water.Regular Replacement: To maintain the filtration effect, it is recommended to replace the filter every 2-4 weeks. If you have multiple pets, please consider shortening your replacement cycle.Warm Tips: Please immerse the filter in water for 2 minutes and rinse thoroughly before use to achieve the best filtration effect and your pet enjoys clean and fresh water.Important Notes: If the pump malfunctions, it may be due to low water level or pet hair debris entering the pump. Please there is enough water or clean the pump promptly.Improved Taste: filters reduce the taste and odor of chlorine found in tap water, which can make the water more appealing to cats. Quantity:A:9 SetColour:As ShownMaterial:non-woven fabricPackage Contents:9 x Cat Water Fountain Filters9 x Sponges Foam FiltersOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is 1-3cm.