Journalist Shigeru Sugawara, who has covered the watch industry for over 30 years, writes in his webChronos series "Swiss Time Travel: Reminiscing on the 1990s." In this eighth installment, he looks at the Caliber 420, a manual-winding version of Zenith's El Primero, one of the world's first automatic chronographs. Along with the "Class El Primero HW" equipped with this rare movement, Sugawara looks back on the company's history of trial and error in branding.
Photographs & Text by Shigeru Sugawara
[Article published on January 3, 2025]
The legendary hand-wound "El Primero"
The 1990s was a time of intense brand restructuring in Switzerland. With the resurgence of mechanical movements, many luxury watch brands, from big names to mid-tier and up-and-coming names, were witnessing trial and error in their branding. Zenith was no exception. Despite boasting a rich history and tradition and boasting outstanding in-house movements like the El Primero and Elite, the brand seemed to struggle to effectively promote its original, appealing products. A magazine reporter covering the 1996 Geneva and Basel watch fairs wrote, "Zenith is a prestigious brand known among watch connoisseurs for producing calibers so exquisite that they supply other companies. For them, this status is half-baked, and they appear to be searching for a way to break away from it" (GoodsPress, July 1996, Tokuma Shoten). The El Primero was best known among watch enthusiasts as the movement used in the Rolex Daytona.
The catalyst for this departure was the Rainbow Flyback, released in 1997. This model added a flyback function to the El Primero chronograph, and as far as I know, it was the only model at the time to feature a 36,000 vph automatic flyback chronograph. Furthermore, since it was developed with the cooperation of the French Air Force and Swiss civilian pilots, it's no wonder that Zenith put special effort into this chronograph. The Rainbow Flyback also featured a striking dial design: bold, angular, and bold luminous Arabic numerals. These numerals closely resemble those that were reinstated in the Pilot collection in 2009. They have their roots in Zenith's legendary pilot's watch, owned by French aviator Louis Blériot in the 1920s.
The legendary "Prime" known only to those in the know
Now, onto the main topic. This time, I'm talking about the manual-winding "El Primero." As you may know, the "El Primero" was one of the world's first automatic chronographs, released in 1969, and was a major player in replacing the manual-winding watches that had been around until then. Zenith also produced a manual-winding chronograph called the "Prime" in the 1990s, known only to those in the know. A magazine article from the time (Goods Press, August 1994 issue) introduced it under the name "Chronograph Prima," but you can now easily find out what this model was like with a simple online search.
The movement is the Cal. 420, a modified version of the automatic El Primero Cal. 400 to be manually wound. The model name "Prime" comes from the "Primero" of "El Primero" with the "ro" removed, meaning the rotor has been removed, creating a play on words. Unlike the classically styled "Chronomaster," the design is inspired by Zenith's military pilot watches from the 1950s and 1960s.
Are manual-winding chronographs rarer than automatic ones?
In the 1990s, the majority of mechanical chronographs were equipped with automatic movements based on the standard ETA7750, and the only notable hand-wound movement was the Omega Speedmaster Professional, which used Lemania movements. The only other option was to search for pre-automatic vintage watches on the antique market. Zenith, under these circumstances, unveiled the Prime at the Basel Fair in 1994, a watch that combined a hand-wound movement with a vintage pilot's watch look. It was reportedly created to meet the demands of hand-wound watch enthusiasts.
However, two years later, in 1996, the popularity of the Prime led to the release of the El Primero, which basically used the same design but reverted from manual winding to automatic. Because it was an automatic, it couldn't be called a Prime. The exterior was Prime, but the name was El Primero. While these modifications of the El Primero from its original automatic to manual winding, and then from manual winding back to automatic, and even changing the name, may seem logical, they must have caused confusion for users. This flexible approach, or, at best, ad hoc watchmaking, was one episode that symbolized the trial and error of the time. Incidentally, subsequent research revealed that the Prime was discontinued in 1997, meaning it ended after just three years.
The quiet rebirth of the El Primero Cal. 420
In 1999, Zenith, along with TAG Heuer and Ebel, became part of the LVMH Group, which established a watch and jewelry division, and began revamping its products to emphasize the brand's distinctive character. Under Thierry Nataf, who became CEO in 2002, the company focused on a new strategy to visually appeal to the appeal of the El Primero. The Chronomaster Open, billed as an "open heart" watch with a window in the dial revealing its beating heart at a high rate of 36,000 vph, was a huge hit worldwide, and became synonymous with the 2000s.
In 2000, before the groundbreaking Chronomaster Open was in the limelight, the Class El Primero HW (then called the Class El Primero HW) equipped with the manual-winding Caliber 420 appeared at the Basel Fair that year. At first glance, I thought it was a reincarnation of the Prime. At the same time, it also looked like a different dial from the 38mm automatic Class El Primero that had been around since the late 1990s. In fact, the case and dial are very similar, so perhaps this Class El Primero was the automatic successor to the Prime. In any case, my first impression was that another confusing model had appeared.
I'm not sure if it was to once again meet the demands of manual-winding enthusiasts, or if it was a brand reform to use up the 1990s Cal. 420, but I can say for sure that the "Class El Primero HW" seemed like an attractive model that I liked. The dial was even bolder than the distinctive pilot's watch style of the "Prime" and its successor, the "Class El Primero," and the luminous Arabic numerals were very similar to those of the "Pilot" model, which was later released in 2009. It also came with a five-link metal bracelet, making it a sporty, slightly cool, and impressive chronograph.
I haven't looked into how long the "Class El Primero HW" was produced after its release in 2000, but I don't think it lasted as long as the "Prime." Perhaps it was a stopgap measure until the "Open" model was introduced, a new approach. Fortunately, I managed to get one before it was discontinued, and I've been wearing it for about 20 years. One day in the 2010s, I showed it to a Swiss Zenith staff member, who surprised me by saying, "I've never seen one in person." Is that true? To put it mildly, it may be a valuable and rare model. Regardless, this watch has several merits. The distinctive design of the Caliber 420 can be seen through the see-through caseback. The sophisticated dial design blends a vintage look with modernity. The case diameter is a comfortable 40mm, and due to its manual winding, it's quite thin at about 11mm. I doubt there will ever be a third hand-wound "El Primero." The now rare Class El Primero HW is also one of the watches that brings back memories of the 1990s for me.
Shigeru Sugawara's profile
Born in 1954. Watch journalist. In the 1980s, he covered France and Italy for fashion and jewelry magazines. Since the 1990s, he has focused on watches, covering the annual watch fair held in Switzerland for over 25 years. He has written and published numerous articles in watch magazines such as "Chronos Japan" and general magazines. He also translates books on watches.
