Premium Granular Activated Carbon Filter Cartridge is made of a highly porous adsorbent material, produced by heating organic matter, such as coal, wood and coconut shell, in the absence of air, which is then crushed into granules. Activated carbon is positively charged and therefore able to remove negative ions from the water such as ozone, chlorine, fluorides and dissolved organic solutes by absorption onto activated carbon. Universal Industry Standard size and is compatible with most industry standard RO Filter units. This item is in the category “Home & Garden\Kitchen, Dining & Bar\Small Kitchen Appliances\Water Purification\Water Filters”. The seller is “filterway” and is located in this country: US. This item can be shipped worldwide.