Protrusions, serving as reference marks for indicating reference positions at which reel strips (106) are to be applied, are provided on three unillustrated reel frameworks. Marks for registration purpose to be aligned with the respective protrusions are provided individually on the respective three reel tapes. At least two reel strips differ in relative position, with respect to a spinning direction of the reels, between the mark and symbols on the reel strips. When the reel frameworks are stopped at rotation detection positions defined by unillustrated sensors, positions of respective symbols on rotation paths defined between the reel frameworks corresponding to at least two reel strips are shifted from each other in the spinning direction of the reels.