Safe and reliable The cat fountain filtration elements are produced in a dust-free environment and packed in an OPP bag to reduce dust and bacteria. They offer a long service life with good cost performance. Triple action filter 1) High density PP cotton traps fur and debris 2) Resin softens water to reduce the risk of lithiasis 3) Activated carbon removes odors Non-toxic and safe for cats, delivering only fresh water. Wide compatibility Fits 1.6 L to 2.4 L drinking fountains and other units of the same size. Dimensions: outer diameter 12.5 cm, inner diameter 3.5 cm. How to use and care Rinse the filters thoroughly with clean water before first use to remove coal dust. Place with the flat side up to ensure the best filtering. Use scenarios - Single-cat households using a 1.6–2.4 L fountain that needs reliable filtration and fresh water. - Multi-cat homes with a shared fountain requiring effective odor and debris removal. - Homes with hard water or noticeable odors, seeking softened water and cleaner-tasting drinking water for pets.