Zenith El Primero: Forty-eight Years Young And Still Going Strong
Presented on January 10, 1969, it was to be the first automatic chronograph ever. The legendary movement took seven years to make. Fully integrated, the construction was built around a column wheel and a central rotor mounted on ball bearings. There would be no additional module. And it was fast. In order to be the most accurate chronograph, it had to beat at a high frequency, and 36,000 vibrations per hour made it the fastest.