Standard filter housings are manufactured of a durable polypropylene or clear Styrene-Acrylonitrile (SAN). All are equipped with 3/4" NPT inlet and outlet ports. Housings are  available in 10" and 20" lengths and will accommodate a wide range of 2-1/2" to 2-7/8" diameter cartridges. The reinforced polypropylene cap offers an optional pressure relief button on the inlet side to relieve pressure inside the housing when changing filter cartridges. Reinforced polypropylene housings have excellent chemical resistance and are ideal for many residential, commercial and industrial applications.