SAYFUT Three-layer Filter Replacement Water Fountain Filters Premium Cotton Activated Carbon Pet Water Filter Premium Activated Carbon + Cotton Pack of 4 Product Description: Efficient Safe and Practical Cats Fountain Filters: Soften the Tap Water and Remove Odors Keep the Water Tasting Fresh- The triple action filter contain 3 different compartments: the ion exchange resin softens the tap water the activated carbon removes the odors and the cotton mesh filters out any sediments the tap water might have.Fits for: YOUTHISAYFUT /HOMMI /ISYOUNG /KOALAD /HAPPYPAPA /PEDY. Environmental Protection Cats Fountain Filters: 4 Pack(The diameter of filters are 5 inches) Replace Them within One to Two Weeks - Please replace the filters once a week thus you are able to save money while taking good care of your cat. Yet if multiple cats are using the fountain more frequent replacement will be necessary. For Your Cat s Health: Not only the filters purify the tap water so that your cats always have safe drinking water but also the better tasting water will encourage your cats to driSAYFUT more helping them replenish moisture and keep healthy. Package Note: 4/ 8/ 12/ 20 PCS Pet Water Filter