Rainfresh BC2 and BC202 heavy-duty activated carbon filter cartridges are high performance high flow 5 micron activated carbon block filters, designed to economically reduce chlorine, taste and odor. These blocks can be run at higher flow rates of 3 US GPM and 6 US gpm respectively. Constructed from high-quality activated carbon, these solid block filter cartridges have much higher surface area (than granular cartridges) and prevent channeling and bypassing for exceptional performance and long life.