A cassette includes: an image capturing unit including: an image receiving unit having a flat panel shape on which a plurality of pixels are arranged on a substrate converting radiation into electric charges and accumulating the converted electric charges and a support to which the image receiving unit is attached and a case in which the image capturing unit is accommodated in an unfixed state, in which the support supports the image receiving unit, and an outer edge of the support is disposed on an outer side of an outer edge of the substrate of the image receiving unit in a direction parallel to an image receiving surface of the image receiving unit.
