Valjoux 726

Higher-beat replacement for the venerable Valjoux 72, operating at 21,600 vibrations per hour rather than 18,000. Produced from 1969-1974. Features the same 9-column wheel design and 3-6-9 subdial layout as the Cal. 72. Used by Rolex as Cal. 727 with Microstella regulator and ROW (Rolex Werke) finishing for later Daytona chronographs. Also used by Certina, Enicar, Eterna, Franck Muller, and Longines. The increased beat rate provided better timekeeping accuracy compared to the original 72.