GAC Series cartridges effectively reduce unwanted tastes, odor and chlorine taste odor from your drinking water.* They are designed to allow maximum contact between the water and carbon, ensuring maximum adsorption. The construction of the cartridge allows water to enter at one end and pass through the entire length of the carbon bed before exiting the other end of the cartridge, while an internal expansion pad minimizes channeling or bypass. Before the water exits the cartridge, a 20-micron post filter helps reduce carbon fines and other suspended particles from the filtered water. The post-filter is permanently fastened to an innovative support basket ensuring that it is firmly secured and eliminating any potential for bypass. GAC Series cartridges are available in a variety of sizes and flow rates, and effectively provide good general- purpose drinking water filtration. * Based on manufacturer's internal testing. Model Micron Rating (Nominal) Filter Life Pressure Drop GAC-BB 20 12,500 Gallons 6 psi @ 2 GPM Materials of Construction : Filter Media Granular-Activated Carbon End Caps Polystyrene Post Filter Spun Polypropylene Outer Casing Polystyrene Expansion Pad Polypropylene