Early Races had been mostly timed by stopwatches mounted to car dashboards, but because the complication was shrunk, they were a lot more typically seen on wrists, especially in the F1 and endurance racing heyday between the ’50s and ’70s. This was the results of intense R&D via the Manufacture, https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/