FILTERPATRONE

A replaceable hollow fiber cartridge filter, including a bundle of hollow fibers (17) of about 8-11 inch length and a porous sleeve (18) surrounding the fibers (17) substantially throughout their length, is positioned in a standardized housing (10) capable of receiving a cartridge of about 2.5 inch O.D. and about 10 to 12 inch length. Cap members (19, 20) are joined to the sleeve at opposite ends, and at least one of the cap members has a coupling (21) for one of a -020 style, -222 style, or a -226 style fitting. Encapsulation seals at least the end of the fibers (17) at the coupling (21) end to one another and to the sleeve member (18) in a fluid tight assembly, while leaving at least the interior of the ends of the fibers (17) adjacent the coupling (21) open.