Early Races ended up generally timed by stopwatches mounted to car or truck dashboards, but because the complication was shrunk, they had been additional usually noticed on wrists, especially in the F1 and endurance racing heyday in between the ’50s and ’70s. Encouraged by British pilot’s watches with the seventies, https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/