The cartridge uses a combination of Granular Activated Carbon. GAC is made from organic materials with high carbon contents such as Wood, Lignite and Coal. Filters are much more tightly packed than GAC filters means that the blocks filter out far more contaminants. Whereas some contaminants may be able to escape the loose carbon found in GAC filters, the compact nature of carbon block filters means that even the smallest particles and contaminants cannot pass through the filter. Effectively reduce Unwanted Tastes, Odor, and Chlorine. Absorbs Chlorine, Halides, Inorganic Contaminants, Odors and other impurities that contribute to bad tasting water.