Compatible with most 1.6L and 2L cat fountains on the market. Note: Does not fit Catit Cat Fountains Pack of 4 Replacement Drinking Fountain Filters. We recommend replacing the filter every 2-4 weeks. Activated Carbon - The filter contains activated carbon which filters out residual chlorine, impurities and odors in the water. Ion exchange resin - The ion-exchange resin in the filter can soften the water, which reduces the risk of kidney stones in the animal. Easy to replace - Rinse the filter with water before replacing it and replace -it every 2 to 4 weeks to keep the water fresh.
