... carbon and filtration treatment. These cartridges eliminate the Activated Carbon Block Filter Cartridges are a one-step carbon and filtration treatment ... " with flow rates up to 2 1/2 gpm per 10" length. These cartridges are designed to be used in either ... ( Polypropylene core ) C. Micron Rating: 5,10,20,25,50,100 D. The Length: 5",10",20", 30" & 40" E.The Diameter ...