“One of the big achievements of this movement,” Barter points out, “is that it managed to integrate all of the chronograph functions and still be automatic, without becoming too chunky.” Whereas this might seem negligeable today, this was an important factor at the time, when svelte watches were the norm. At just 6.5mm in thickness, the El Primero managed to come in slimmer than the Lemania 2310, a manual-wind calibre, and the micro-rotor movement developed by the Chronomatic group the same year.
While this advancement in horology was impressive, it felt somewhat short lived, as Quartz technology was just around the corner. The mechanical chronograph would soon go from a functional tool, to an inferior relic, “making these new chronographs rather surplus to requirements,” as Barter puts it. Zenith first fit the El Primero movement inside the A384 and A386 models, but they never really took off, due to the seismic shift taking place in the industry at the time. This, in part, led to Zenith and Movado, who had formed a small group at the time, being sold off to an American company. So, while their watches were still made in Switzerland, all of the administration moved State side.