This high-performance 20-inch catalytic carbon water filter cartridge will remove harsh chloramine chemicals that cannot be properly treated by basic activated carbon filters. Using state-of-art catalytic carbon media, this filter retains all of the adsorptive properties of activated carbon, but it also has the unique ability to promote or catalyze chemical reactions. This dual water purification process makes catalytic activated carbon the most effective media available for the removal of chloramines and hydrogen sulphide from water supplies.