Ralco
Ralco was a watch brand located in La Chaux-de-Fonds from the 1920s to the 1960s. The brand is most famous for producing the first rattrapante wristwatch in the 1920s and was a subsidiary of Movado for most of this time.
It is widely reported that Ralco introduced the world's first rattrapante chronograph wristwatch in 1921, though there is very little evidence of this today. Indeed, Ralco is not listed in Indicateur Davoine until 1924 (as "R A L C O") and there is no mention of such a patent or product from the company in that decade. Research shows a similar advertisement in Revue International d'Horlogerie in 1919 and similar advertisements for rattrapante watches from Nathan Weil as early as 1913.
It appears that Ralco was little more than an export division of Movado. For many years, at least from 1927 through the 1940s, Ralco was located at Rue du Parc 119, next door to Movado at 117. But these addresses were often reversed, and by the 1960s both firms shared the 119 address.
Ralco was one of the brands purchased by Zenith Time in 1972, along with Martel, Movado and Dovado, and Mondia. Ralco continued to exist in some form through the 1980s, though not as a watch brand.