A filter assembly includes a housing, a proximal end cap, and a nut plate. The housing defines a longitudinal axis and includes an inner surface surrounding the longitudinal axis. The proximal end cap is disposed within the housing and defines a central aperture. The nut plate is disposed within the housing and includes a flange portion and an outer wall. The flange portion is disposed within the central aperture. The outer wall includes a plurality of protrusions disposed about the longitudinal axis. At least one of the plurality of protrusions engages the inner surface to prevent rotation of the nut plate relative to the housing.