Patent ID: 8070940

Claim:
A fuel filter device comprising: a filter element formed from a filter material configured to capture a foreign substance from fuel; a component including a capturing material to capture matter from fuel; a housing; and a lower case being attachable to and detachable from a bottom portion of the housing in a movable direction, wherein the housing and the lower case are configured to accommodate the filter element and the component, the filter element defines a passage, which extends through the filter element in the movable direction, the passage is configured to accommodate the component, the component is configured to be attached to and detached from the housing together with the lower case when the lower case is attached to and detached from the housing, the component is connected to the lower case, the component and the lower case therebetween have a connecting portion including at least one fitting portion and at least one opening configured to be connected with each other, each of the opening has first, second, and third portions arranged in a circumferential direction, the first, second, and third portions respectively having first, second, and third widths in a radial direction, each of the fitting portion has a fitting-portion width in the radial direction, the first width is larger than the fitting-portion width, the second width is smaller than the fitting-portion width, and the third width is between the first width and the second width.