The Cal. 48 family from Hahn & Cie., a historic watch movement located in Le Landeron, began in 1937 with Cal. 47, the world’s first cam-switching chronograph movement. A long series of iterations gave rise to one of the most popular chronograph movement lines in history, with over 3.5 million examples produced over four decades. Many were simple and inexpensive movements, but some added date, calendar, and moon phase complications and found use in higher-end watches. The Heuer Carrera is perhaps the most famous watch to use Landeron’s cam switching movement, but it was also found in chronographs from Baume & Mercier, Edox, Favre-Leuba, Glycine, Helvetia, Nivada, Titus, and Zodiac. Even Lemania and Leonidas, known for their own movements, used Landeron chronograph calibers.