A flexible printed circuit board includes: a proximal end portion; a left strip portion and a right strip portion that extend in the rear direction from the proximal end portion; and conductive paths, a portion of which is provided spanning from the proximal end portion to the left strip portion, and another portion of which is provided spanning from the proximal end portion to the right strip portion. In portions of the conductive path in the left strip portion and the right strip portion, strip side connecting portions that are electrically connected to electrode terminals of electricity storage devices are provided. In the left strip portion, a deformation portion that deforms to increase the distance between the left strip portion and the right strip portion is provided.