Pentair® Pentek® DFX Series Diamond Flow™ premium cartridges utilize several of the Pentair core competencies by merging technologies into one cartridge in order to bring customers a quality product. The cartridges offer the effective chlorine taste and odor reduction found in traditional Pentek carbon blocks, combined with the superior sediment reduction to resist premature plugging. These dual-purpose cartridges are well-suited for a wide range of applications. http://www.pentairaqua.com/pro, (800) 279-9404