These spools contain small round pellets of gold that rattle. Such rattles are usually found in pairs, and most come from the eastern Mediterranean region. It is not known exactly how they were used.
Metropolitan Museum of Art. 1986. "One Hundred Sixteenth Annual report of the Trustees for the Fiscal Year July 1, 1985 through June 30, 1986." Annual Report of the Trustees of the Metropolitan Museum of Art, 116: p. 29.