Silver fitted, Mastodon Ivory tip Arcos Brasil Special Edition Silver bows are completely hand made, including the frogs, by a master bow maker. Makers of Special Edition bows have had the privilege to apprentice under the guidance of Mr. Pierre Guillaume at his atelier in Brussels.The finest choice of pernambuco wood is used on these bows. The frogs have a distinct style and are individually made from high quality ebony, fitted with sterling silver and beautiful abalone details.