Glycine is a Swiss wristwatch manufacturer. Glycine became a noteworthy watch maker in the early 1950s for the introduction of their Airman model, a 24 hour watch favored by both military and commercial pilots. The Airman was worn by many U.S. Air Force pilots during the Vietnam War. Glycine still makes several variants of the Airman. Other models in the Glycine line include the Incursore, Combat, and Lagunare series.