DuPont WFPFC5002 Universal Whole House Poly Block Cartridge, 2-Pack Includes 2 universal 10-inch cartridges that fit all DuPont Whole House Water Filter Systems and most other brands of standard-size systems Impoves taste and odor of water; effective in reducing rust and sediment Filters up to 15,000 gallons for home or office Each cartridge lasts up to three months, Micron nominal: 10