5 Stage Reverse Osmosis Filter Replacement Set, gac, carbon and sediment FEATURES 10-Inch Sediment filter 5 Micron, 10-Inch Carbon block filter 5 Micron & 10-Inch Granular activated carbon filter KEEPS WATER FRESH - Reduces sediment, scale, rust, dirt, coarse sand, sand, fine sand, extra fine sand, silt IDEAL for a standard Reverse Osmosis Water Filtration Unit or any type of Water Filtration Unit with 10" housing FILTER LIFE 4 month or 12,000 gallons: Replace two or three times a year, depending on the water quality MEETS NSF STANDARDS and REGULATIONS FEATURES 10-Inch Sediment filter 5 Micron, 10-Inch Carbon block filter 5 Micron &amp; 10-Inch Granular activated carbon filter KEEPS WATER FRESH - Reduces sediment, scale, rust, dirt, coarse sand, sand, fine sand, extra fine sand, silt IDEAL for a standard Reverse Osmosis Water Filtration Unit or any type of Water Filtration Unit with 10&#034; housing FILTER LIFE 4 month or 12,000 gallons: Replace two or three times a year, depending on the water quality MEETS NSF STANDARDS and REGULATIONS