The Pentek RFFE-10BB Iron Reduction Big Blue Filter Cartridge Reduces up to 3 ppm of dissolved iron from water. For use in 10-inch Big Blue filter housings.Genuine Pentek RFFE-10BB Big Blue (10" x 4.5") Filter cartridge for iron reduction, helps to eliminate the orange and brown rust stains in your toilets, showers, tubs, sinks and your other plumbing fixtures in your home. Reduces up to 3 ppm of dissolved iron from water. For use in 10-inch Big Blue filter housings. 8 GPM flow rate. ? The RFFE-10BB filter cartridge is designed to provide an easy and effective method of reducing iron from water, which greatly improves the taste. ? The RFFE-10BB filter adds no harmful chemicals to your water, so it is completely safe to drink. ? Easily and effectively reduces up to 3 ppm of dissolved iron from water. Improves flavor and reduces the metallic taste caused by iron. Reduces the possibility of pipe and water heater damage. For use in Pentek 10-inch Big Blue filter housings. A pre sediment filter is recommended to lengthen the life of this filter as heavy sediment can plug this filter up.