" Initially, These wristwatches were being one-off or custom creations that often looked a whole lot similar to the pocket watches from which they progressed. But before long, wristwatches took on their own aesthetic, with their unique specialized innovations to unravel new complications offered by wrist-borne timekeepers. Gucci started off https://www.watchesworld.com/a-history-of-watch-reference-numbers/