

The big question was how Zenith would celebrate such an important anniversary. It has gone on to become one of the most storied movements of the 20th century and, despite briefly going out of production, it's been a mainstay in Zenith's arsenal for almost its entire lifespan.

Sure, there were other automatic chronographs unveiled that year, but Zenith's was the only one to feature a high-speed 5 Hz (36,000 vph) escapement for greater precision and accuracy. The incredible movement and the watch that introduced it to the world – the A386 – changed the game entirely back in 1969. This year's biggest horological anniversary might be the 50th birthday of the Zenith El Primero.
