DuPont WFQTC70001 Quicktwist Carbon Block Filter Cartridge Carbon block filter for use with DuPont Quick Twist Drinking Water Filtration Systems Reduces heavy metals, VOC's, cysts, chlorine, silt, rust and sediment in drinking water QuickTwist change system with auto shut-off for easy cartridge replacement Filters up to 500 gallons; lasts up to 6 months Food and beverages taste better when made with filtered water