Convex bronze disks, often with punched or incised ornament, were frequently attached to wooden, leather or bronze shields. They were probably made for ceremonial or funerary purposes since they are too fragile to have any practical use in combat.
von Bothmer, Dietrich and René d'Harnoncourt. 1950. Greek, Etruscan, and Roman Antiquities: An Exhibition from the Collection of Walter Cummings Baker, Esq. no. 6, p. 7, New York: Walter Cummings Baker.
de Puma, Richard Daniel. 2013. Etruscan Art in the Metropolitan Museum of Art. no. 3.14a, pp. 36, 299, New Haven and London: The Metropolitan Museum of Art.