Early Races have been mostly timed by stopwatches mounted to auto dashboards, but because the complication was shrunk, they have been extra frequently witnessed on wrists, particularly in the F1 and endurance racing heyday between the ’50s and ’70s. Inspired by British pilot’s watches from the 1970s, Hamilton’s Khaki Aviation https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/