This 20 inch blue housing with a black cap accepts Full Flow filters. The housing cap features a 1 1/2 inch NPT pipe size connection with a pressure relief valve. A leak-proof sealing is accomplished by compression against a top seated EPDM O-ring located in the housing''s sump. The heavy duty construction is made using high quality FDA grade polypropylene. It has a superior chemical resistance from many aggressive chemicals. The thick side walls and buttress thread design allows for superior sealing and security. It is rated at temperatures up to 125 F (52 C). The water pressure is rated up to 125 PSI (8.75 BAR).