Water Filter Cartridges are made for great-tasting water. The filters are d and certified by WQA against NSF/ANSI 42, 53 and 401 for the reduction of: Chloramine (taste and odor); Clorine (taste and odor); Mercury; Copper; Cadmium; Benzene; Zinc; 1, 2, 4-Trichlorobenzene; Estrone; Meprobamate; Trimethoprim. For optimum performance, prep your water filter before using and change your water filter cartridge after 40 gallon (151L) or approximately once every 2 month for an average family. To prep the new filter before use follow these steps. 1. Immerse the water filter cartridge in cold water for a few seconds. Shake it gently while submerged to remove any air bubbles. Discard the water. 2. Place the water filter cartridge in the reservoir opening. Press water filter cartridge down firmly. Ensure the water filter cartridge seats completely in position. Rotate if needed. 3. Fill the reservoir with cold tap water and allow the water to filter through. The first two fillings will contain filter media sediment and should be discarded. This is normal. Refill the reservoir and the system is ready to use. Features: Reduces Chloramine (taste and odor) Reduces Chlorine (taste and odor) Reduces other substances that may be in your tap water such as Mercury, Copper, Cadmium. Benzine, Estrone, Meprobamate and Zinc 11.61 L x 2.56 W x 11.02 H 2.39 lbs