The PureT GCB series are the finest melt-blown polypropylene sediment depth filters with the best filtration efficiency in the industry. The 2-1/2-inch diameter GCB series are both constructed with multi-layers and manufactured by a unique melt-blown process. Beyond the specifications of ordinary sediment depth filters made of only two or three layers, the PureT GCB series exceed industry standards with a true gradient density four-layer structure from the outer to the inner surface. This patented four-layer design combined with the unique manufacturing process achieves three to eight times the dirt-holding capacity than similarly sized standard sediment cartridges. High quality construction and unmatched performance make the PURET GCB series excellent choices for all residential, commercial, and industrial applications. Additional Details ------------------------------ Product description: The PureT GCB series are the finest melt-blown polypropylene sediment depth filters with the best filtration efficiency in the industry. The 2-1/2-inch diameter GCB series are both constructed with multi-layers and manufactured by a unique melt-blown process. Beyond the specifications of ordinary sediment depth filters made of only two or three layers, the PureT GCB series exceed industry standards with a true gradient density four-layer structure from the outer to the inner surface. This patented four-layer design combined with the unique manufacturing process achieves three to eight times the dirt-holding capacity than similarly sized standard sediment cartridges. High quality construction and unmatched performance make the PURET GCB series excellent choices for all residential, commercial, and industrial applications.