Four-Stage Purification System Reduces Contaminants Such As Arsenic, Fluoride, Bacteria, Virus, Lead, Mercury, Chlorine, Chloramine, Select Pharmaceuticals And More;Reduces Over 95% Of Perfluorooctanoic Acid (Pfoa) And Perfluorooctane Sulfonate (Pfos) In Drinking Water;1:1 Ratio High-Recovery Reverse Osmosis Membrane Creating Less Waste Water;Provides Up To 27.5 Gallons Per Day, Or The Equivalent Of Over 200 16.9-Oz. Bottles Of Water (Results May Vary Based On Water Pressure, Temperature And Incoming Water Quality);0.5 GPM (1.9 L/Min) Maximum Flow Rate At 60 PSI (4.1 Bar);3.2 Gallon Storage Tank;Filter Head Automatically Turns Off Water Supply When Cartridge Is Removed;Postage-Paid Recycling Program For Used Cartridges To Reduce Solid Waste To Landfills;Requires Kohler Ro-Compatible Beverage Faucet With Air Gap;For Cold Water Use Only;Includes Four Filter Cartridges (K-22156, K-22157, K-22158, K-23334).