Abstract: A filter of the throw away spin-on type having a housing body with a closed end and an open end, a filter element mounted within said body, a cover plate secured to and closing said open end, a gasket retainer secured to the end closure cover plate, fluid input and output apertures provided in both the cover plate and the gasket retainer, the gasket retainer having a recessed pocket extending circumferentially around the fluid flow openings, inwardly of the outer circumference of the gasket retainer, said gasket pocket having a base at a specified angle relative to the surface plane of the cover plate, and a resilient flexible gasket member of special shape retained by the gasket retainer pocket. The specially configured sealing gasket member is preferably of rhomboid shape and thus a cross section thereof forms a parallelogram with oblique angles and opposite sides equal. The top and bottom surfaces of the sealing gasket form an angle of approximately 10.degree.