This helmet is decorated with engraved bands separated by plain fillets. There are the emblems of the Borromeo family, like the unicorn and the bit of a horse, the motto “Homylitas” and Saint Justine, claimed by the family as an ancestor. The helmet belongs to a suit of armour probably made for Renato I Borromeo (1555- 1608), who became a military captain in 1591 and ambassador to King Philip III of Spain in 1598. He was the brother of Cardinal Federico Borromeo.
The decoration was engraved by etching, subsequently partly darkened and gilded. Other parts of the same suit of armour, bearing the mark of Pompeo della Cesa, are now in the Museo Stibbert in Florence.