Zenith El Primero Stratos Flyback Striking 10th
Why We Love it
Why We Love it–
The El Primero was the culmination of a years-long research and development process undertaken by Zenith to develop the world’s first automatic chronograph movement.
Zenith announced the El Primero at a press conference on January 10, 1969. This was four years later than Zenith had intended —the brand had begun developing the caliber in 1963, hoping to bring it out for Zenith’s centennial in 1965. Nevertheless, on that winter day in 1969, Zenith proudly displayed a working model of its chronograph. And the rest, as they say, is history.
Fast forward to the 1990s, and Zenith was once again pushing the limits of what a contemporary chronograph could be and do. The company combined the El Primero’s impressive automatic movement with flyback capabilities, allowing the wearer to instantaneously reset the central chronograph seconds hand to zero and begin timing a successive event with the push of a single button. The resultant watch, dubbed the Zenith Rainbow, was a special commission for the French armed forces.
In the early 2010s, Zenith adopted this technology to a civilian timepiece, which it dubbed the El Primero Stratos Flyback Striking 10th. Combining the flyback movement El Primero 4057 (an evolution of the Rainbow’s caliber 405) with a 1/10th-second chronograph feature that whips the second hand around the dial once every 10 seconds — plus a tri-color dial recalling the El Primero watches of the 1960s and 1970s — it represented the culmination of all Zenith had developed in automatic chronograph technology up to that point in time.
This particular El Primero Stratos Flyback Striking 10th is housed in a 45.5mm stainless steel case with a sapphire crystal, a signed crown, ‘doorstop’ pushers, and a black ceramic unidirectional count-up bezel. It features a sunburst silver and black dial with applied indices, a matching ‘sword’ handset, a date window above 6 o’clock, and a tri-color, triple-register chronograph layout in blue, brown, and grey. Powered by the automatic Zenith El Primero Calibre 4057, it’s paired to a stainless steel multi-link bracelet with a signed, push-button deployant clasp. What’s more, it’s in mint condition with its factory stickers intact, and ships with its factory goodies.
Zenith's chronographs in particular gained a reputation for excellence. At first Zenith used Excelsior Park and Valjoux movements, sharing them with Universal Genève and Movado (with which Zenith would merge for a time in 1969). By the 1960s Zenith acquired ébauche manufacturer Martel and began using their movements exclusively, leading to lauded calibers such as the 146HP and 146DP, which launched in 1969.
1969 was a banner year for horology, as it saw the launch of the first automatic chronograph movement. This was a race between a team consisting of Hamilton, Heuer, Buren, Dubois-Depraz, and Breitling; Seiko; and Zenith. Zenith used the Caliber 146 as a basis for the caliber which the brand would dub "El Primero" — "the first." Of the consortium’s Caliber 11, Seiko’s reference 6139, and the El Primero, only the latter feature a “high-beat” movement for increased accuracy.
Zenith ceased using manually-wound movements in their chronographs after the introduction of the El Primero — however, then the Quartz Crisis of the 1970s hit, and the company was sold. Employees were ordered to destroy or otherwise liquidate their mechanical watchmaking tooling, but incredibly, one daring engineer, Charles Vermot, decided to hide machinery behind a false wall that he built himself in the attic of the company’s manufacture in Le Locle. He told no one about what he was doing — not even his family.
Then, in the 1980s after the company had changed hands once again, he led modern Zenith management to this secret cache of horological wonders, in which the El Primero tooling was hidden. Ebel placed the first modern order for El Primero movements in 1984, but it was Rolex, who ordered thousands of calibers to power their new automatic Daytonas, that saved the firm. Today, the El Primero powers numerous vintage-inspired chronographs as well as the new Chronomaster Sport, a watch aimed as a competitor at — with much irony — the Daytona.
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Since our pieces are vintage or pre-owned, please expect wear & patina from usage and age. Please read each item description and examine all product images.
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Shipping & Returns
Shipping & Returns+
All of our watches include complementary insured shipping within the 50 states.
Most of our products are on hand and will ship directly from our headquarters in New York City. In some cases, watches will be shipped directly from one of our authorized partners.
We generally ship our products via FedEx, fully insured, within 5 business days of purchase. An adult signature is required for receipt of all packages for insurance purposes. Expedited shipping is available at an additional cost. We are also happy to hand deliver your purchase in Manhattan or you may pick it up at our showroom.
Returns must be sent overnight or by priority international delivery, fully insured and paid for by the customer. A restocking fee may apply. Watches must be returned in the same condition as initially shipped.
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Zenith El Primero Stratos Flyback Striking 10th