• Replacement filters designed for cat water fountains, compatible with Pixi 43717 and 43722 2.5 L models • Made with high food-grade coconut shell activated carbon, providing deep filtration and improving water clarity • Four-layer filtration system: the high-density cotton layer traps hair and fine debris, while the activated carbon and ion exchange resin remove most impurities, heavy metals, and odors, offering fresher water for pets • Each filter comes in individual packaging to ensure hygienic storage • Easy to use: it is recommended to wash the pads before use and replace them every 2 to 4 weeks to maintain water quality