On January 12, 1979, the Swiss watch industry announced the thinnest watch ever made: The Delirium, developed by Ebauches SA for Concord, Eterna, IWC, and Longines, measured just 1.98 mm thick. It wasn’t a big seller, but was a PR exercise to show the world that the Swiss were innovating like the Japanese. And the novel design paved the way for another announcement four years later, the Swatch.