A reusable filter cartridge includes a base cup having a sidewall defining a plurality of openings that are covered with a filtering material. A bottom wall of the base cup defines impermeable outlet probe receptacles sized and positioned to receive an outlet probe of a brewing device. Two or more adapter rings removably secure to the base cup thereby defining multiple combinations with differing volumes for use in different brewing devices and for preparing different numbers of servings. An adapter ring for multiple-serving implementations may include a tube along the side thereof with a bottom opening located below the lowermost surface of the adapter ring. An insert secures within each adapter ring and defines an inlet probe aperture and structures for creating a seal with respect to an inlet probe of a brewing device.
