Pentair Pentek CBC Series Cartridges are bonded powdered activated carbon (PAC) blocks that reduce unwanted bad taste and odor and chlorine taste and odor from potable drinking water. The CBC-20 carries a nominal 0.5 micron rating, pairing fine filtration with high-capacity taste and odor reduction for residential, food service, commercial, and industrial use, including as a polishing filter or pre-filter. The CBC-20 measures 2.88 inches by 20 inches and fits standard 20-inch filter housings. With an initial pressure drop of 17 psi at 2 gpm and a temperature rating of 40 to 180 degrees F, it maintains steady flow along with enhanced dirt-holding capacity. The cartridge is tested and certified by NSF International to NSF/ANSI Standard 42 for material requirements. The longer 20-inch format gives this cartridge a high service life rated for more than 45,000 gallons of chlorine taste and odor reduction at 2 gpm. Replace the cartridge when you notice a drop in water pressure or water quality. After installation, flush the cartridge before use to clear any carbon fines.