DGD Series Cartridges are manufactured from 100% pure polypropylene and are sized for use in Pentair Pentek 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 compatibility. 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. The larger diameter of the filter reduces the particle load, allowing it to operate at higher velocities. The effective filter depth is increased to a full 233%, providing very high particulate reduction efficiencies and added loading capacity. The design and performance characteristics of the DGD Series Cartridges make them an excellent choice for all residential, rural, municipal, and commercial applications. This 2-pack of DGD-2501-20 cartridges provides 1 micron filtration in the 20" x 4.5" Big Blue format.