The 13.33Z was developed in 1913 and featured 18 jewels, a diameter of 13 lignes (29 mm) and height of 6 mm, beat at 18,000 vph and utilized a Breguet hairspring. It had a crown that was used for winding the watch and served as a pusher for the chronograph. The first push starts the chronograph, the second stops it, and the third resets, and the cycle repeats. This was the first chronograph wristwatch movement.


in 1936 Longines began to produce one of the most technologically advanced chronograph movements at the time the Caliber 13ZN. As we mentioned at the beginning, Longines developed the first chronograph for the wristwatch the 13.33Z but this was the first chronograph mechanism equipped with the flyback, or retour-en-vol, function. The 13ZN had 17 jewels; a diameter of 29.80 mm and height of 6.05 mm, and beat at 18,000 vph, and was equipped with a Breguet hairspring.


In 1947, Longines followed up with what many regard as one of the finest and most beautiful wristwatch chronograph movements ever, the Caliber 30CH.