The Hydronix SDP-2520 radial flow carbon Filter are 20 inch x 2.5 inch dual purpose filters. They filter down to 25 microns and are perfect for compact filtration needs where only one housing is used. This 2 stage in one filter has a 25 micron sediment outer core with GAC Coconut Shell Carbon media in its center. The filter has a 3rd layer of 5 micron Polypropylene at its core to reinforce the filter and further filter contaminants. Effectively Reduces: - Sediment ; Organics ; Chlorine Taste & Odor ; Bad Taste & Odor. Specifications: - Filter Media: Granular activated carbon ; Applications: City or well water ; Dimensions: 20" L x 2-3/4" D ; Micron Rating (Nominal): 25, Initial ΔP (psi) @ Flow Rate: 0.6 psi @ 2 gpm ; Temperature Rating: 40°F to 125°F ; Compatible Part or Model Numbers: - Part Number: 155065-43 ; 15506543 ; 155065 ; Ametek RFC20 ; Pentek RFC20 ; USFilter, US Filter RFC20. Compatible Housings: - Culligan ; Ametek ; Pentek #20 ; 20" standard filter housings (20-ST, 20-3GMB-C) ; Ametek, Bruner, Cuno, Harmsco, Hydronix, Keystone, Kleen Plus, Plymouth Products, USFilter, Water Resources, and many other brands that use 20"x 2.5" standard size filters.