Granular Activated Carbon filters (GAC) – GAC filters are well-known for their highly efficient reduction of chlorine taste and odor, as well as other taste and odors of many organic chemicals and volatile organic compounds. All GAC filters are made with high quality coconut shell carbon. Micron rating: 5 Micron. Dimensions: 9.75†x 2.5†Lifetime: Replace once or twice a year, depending on the water quality. Block Activated Carbon filters – Block Carbon Filters are similar in their performance to that of GAC filters, being made of fine coconut shell carbon they also do remove odors and tastes of many organic compounds, chlorine especially. Though, because this filters are made of a packed carbon (forming a cylinder block), they offer a much finer filtration of suspended particles and dirt. Micron rating: 5 Micron. Dimensions: 9.75†x 2.5†Lifetime: Replace once or twice a year, depending on the water quality. Melt-blown Polypropylene Sediment filters – Sediment filter is often the first filter installed in the Reverse Osmosis circuit. Sediment filters are made of fine melted polypropylene, which is then blown and spun in a cylinder-like form. The main function of a sediment filter is to remove large and fine particles from a drinking water, such as sand, dirt, silt, and rust particles. Removal of such particles allows for a better performance of all the following filters, such as Carbon Block or GAC filters. Micron rating: 5 Micron. Dimensions: 9.75†x 2.5†Lifetime: Replace two or three times a year, depending on the water quality. All Filters are individually wrapped and sealed.