Ring aryballoi figure quite prominently in Corinthian pottery from the seventh through the sixth century B.C. They are rare in other Greek regions and were originally introduced from the East. This example may be an Etruscan imitation.
Metropolitan Museum of Art. 1981. "One Hundred Eleventh Annual Report of the Trustees for the Fiscal Year July 1, 1980 through June 30, 1981." Annual Report of the Trustees of the Metropolitan Museum of Art, 111: p. 36.
von Bothmer, Dietrich, Carlos A. Picón, Joan R. Mertens, and Elizabeth J. Milleker. 1993. "Recent Acquisitions: A Selection 1992–1993: Ancient World." Bulletin of the Metropolitan Museum of Art, 51(2): p. 60.