This is a classic Simplex trademark. The claimed date of first use in France is December 1929, and the claimed date of first use in commerce with the US is March 1939 - which is a good match with the date of Simplex’s first US patent.

• Publisher: US Patent and Trademark Office
• Inventor: Lucien Juy, doing business under the name Etablissements “Le Simplex”
• Country: USA
• Date: First use December 1929
• Derailleur brands: Simplex
• Derailleurs: nothing specific