At first, the movement was simply called 12/13, but later it was christened caliber 42. From the outset, it was available with 1 or 2 pushers and with 30 or 45-minute counters.
A few years later, a classic, round version of this movement appeared, christened caliber 4, and a version with a caliber 4 hour counter, under the name 42.
But if this movement was so widespread, it wasn't just used by Excelsior Park. Three other companies used it: Gallet, Zenith and Girard Perregaux.
- Gallet had a strong presence in the United States, where watches were sold under the Gallet and Racine brand names. Gallet counters were equipped with Excelsior Park calibers. For chronographs, Gallet used Excelsior Park calibers and calibers from the Ébauches SA trust (Vénus and Valjoux in particular).
- At the time of the creation of the Swiss watchmaking trusts in the late 1920s and early 1930s, Zenith chose to remain a manufacture, and thus to continue producing its own calibers. Because of its watchmaking status, the company could not use Ébauches SA calibers (Vénus, Landeron, and Valjoux from 1944). To make its first wrist chronographs, in 1938 Zenith turned to Excelsior Park, which was also a manufacture, and used the caliber 42. Later, as a result of the relationship between Zenith and Universal, Zenith would also use Universal/Martel calibers for its chronographs [13].