PURPOSE: To obtain a cup supporting section simple in construction and rare to be broken by forming recessed step sections on the upper surface of the surrounding wall of a storage room and forming multiple round holes storing cups at positions corresponding to the recessed step sections of a hatch covering its opening section.

CONSTITUTION: Recessed step sections 12b' are formed at part of the upper surface of the surrounding wall 12 of a storage room such as a fuel tank. The upper surface of the opening section of the surrounding wall 12 is covered with a hatch 11 so as to be freely opened or closed. Multiple round holes 11c storing cups are formed at positions corresponding to the recessed step sections 12b' on the surrounding wall 12 of the hatch 11. Accordingly, the cup mount section is never broken even if a person is seated, and cups can be reliably held.