Abstract: A filter housing is disclosed. It is preferably used to house membrane filters supported on plates. The base, top and a two-way cap cooperate to form a pressure-tight vessel. The top can be moved vertically to permit use of various numbers of filters and support plates in the housing without requiring spacers or spacer tubes. The structure of the housing is such that all surfaces exposed to liquid are free of screw threads or other surface configurations which are not readily sanitizable or sterilizable, particularly by autoclaving. Also, since the tightening mechanism is outside the filter enclosure, the filters can be sterilized by autoclaving and subsequently tightened into position.