Filtrete Large Capacity Granulated Activated Carbon Whole House Water Filter 4WH-HDGAC-F01 helps reduce chlorine taste and odor as well as particulate and rust providing clearer more appealing water throughout the whole house. The carbon filter cartridge provides a high flow for your household water for drinking washing toilets shower and more. It should be replaced every six months or sooner if a noticeable reduction in flow rate occurs.. It uses granular activated-carbon media to reduce chlorine taste and odor has a 25-micron filtration rating for particulate reduction and a flow rate of 10 gallons/38 liters per minute. It is certified to NSF Standard 42 for material safety requirements. It is for use with Filtrete™ Large Capacity Whole House Filtration System 3WH-HD-S01 or similar 1-high large diameter drop-in housings.