This late 1940s (1947?) Italian catalogue lists four derailleurs:

• Campagnolo Corsa
• Simplex Campione del Mondo
• Simplex Tour de France
• Vittoria Margherita.

The interesting one is the Simplex Campione del Mondo, which was a French design that had begun to be manufactured in Italy.

• Publisher: Giuseppe Rossi
• Country: Italy
• Date: 1947?
• Derailleur brands: Campagnolo, Simplex, Vittoria
• Derailleurs: Campagnolo Corsa, Simplex Campione del Mondo, Simplex Tour de France, Vittoria Margherita