This iSpring FC15 carbon block CTO filter cartridge reduces fine sediment and chlorine taste and odor in drinking water. It has a nominal (85%) filtration rating of 5 microns. The filter will reduce free available chlorine (FAC) at 2 parts per million (ppm) by at least 90% in up to 6,000 gallons at a flow rate of 1 gallon per minute (gpm). This cartridge is made of bonded powdered activated carbon (PAC) filter media wrapped in a polyolefin pre-filter with polyethylene outer netting. The cartridge has an initial pressure drop of 3.4 pounds per square inch (psi) at a flow rate of 1 gallon per minute (gpm), and operates over a temperature range of 40 to 180 degrees F (4.4 to 82.2 degrees C). This carbon block filter cartridge meets National Sanitation Foundation/American National Standards Institute (NSF/ANSI) standard 42 for quality assurance, and is used for purification of residential and commercial drinking water.