This listing is for 8 filters.Removes Dirt, Rust & SedimentGradient Density Sediment Cartridge75 Micron Filtration75/25 Micron Removal of Dirt, Rust & SedimentBB/Full Flow Size 10" × 4.5" Sediment CartridgeDGD Series cartridges are manufactured from 100% pure polypropylene and are sized for use in our Big Blue filter housings.DGD Series cartridges are designed for purity and will not impart taste, odor or color to the liquid being filtered. Additionally, the polypropylene construction provides superior chemical resistance and is not prone to bacterial attack.The DGD Series' advanced design combines selective final filtration with appropriate pre-filtration to achieve up to three times the dirt-holding capacity of similar size sediment cartridges and even greater capacity than standard spun or string-wound cartridges. This performance enhancement is achieved by combining two separate gradient layers in one filter.The larger diameter of the pre-filter reduces the particle load to the post filter, allowing it to operate at higher velocities. The effective filter depth is increased to a full 233% of standard spun-polypropylene or string-wound filters. This increased depth provides for very high particulate reduction efficiencies and added loading capacity.The unique design and performance characteristics of the DGD Series cartridges make them an excellent choice for all residential, rural, municipal and commercial applications.