These days, the focus seems to be on whopping power reserves and in-house calibers, with even mid-tier brands jumping on the bandwagon. But if you know your vintage watches, you’ll be aware of a time when everything wasn’t measured in the number of bridges, cogs, and pinions a brand produced by itself. In the car world, the image is more realistic. Even a few years before the increased sharing structure brought on by electric tech, BMW set the bar for in-house production with what was considered a very high 40%. With all the focus on in-house excellence and alternative chronometric certifications, I’m feeling drawn to a fairly simple yet sturdy ETA movement. The 7001 has been in production since 1971, and it is seeing a resurgence, even a Peseux revival of sorts.



The backstory of the ETA/Peseux 7001 is fascinating. Fabrique d’Ébauches de Peseux, S.A. — or just Peseux for short — was the name of a movement manufacturer founded in 1923 and acquired by ETA in 1985. One of its most famous calibers was the 7001, a hand-cranker with an ultra-slim profile. The first shock to your system, unless you’re used to vintage watches, will be the lack of hacking seconds. But to me, that’s a minuscule price to pay for the effortless slenderness. It has an everyday-spec 17 jewels and a lithe 2.5mm thickness. That is seriously thin for a movement that has been in production since 1971. Well-known vintage calibers, such as the Omega 651, used the Peseux 7001 as a base, as did Nomos for many of its 1990s references.



Now jump to the modern era, where the Omega Speedmaster Racing Co-Axial Master Chronometer Chronograph 44.5mm Men’s Watch O32923445106001 represents a completely different philosophy. While the Peseux 7001 celebrates minimalism and hand-wound charm, this Omega is a bold, automatic chronograph equipped with the Co-Axial escapement and Master Chronometer certification. It is a tool built for precision and durability, not for ultra-thin elegance. Here we see the polarity of horology: one movement (the 7001) that powers a wave of slim, affordable watches from brands like Zelos, Maen, Baltic, Ming, and Holthinrichs; and another (the Omega 9900 caliber family) that drives a heavyweight icon of motorsport history. Both have their devoted followers.



The Zelos Nova 37mm is a perfect example of the 7001’s appeal. My Peseux-powered Holthinrichs Ornament and this small Zelos nugget of tantalum inspired this story. If you haven’t tried on a watch with a tantalum case, you’ll be in for a weighty surprise. The metal is rarer than gold on our planet and just as heavy while channeling the dark color of titanium. Elshan replica patek-philippe watches Tang of Zelos created a version of his new Nova 37mm in this stealthy metal. It’s packed with material value, and I bonded with it. I almost bought the loan watch at full price. After 4–5 weeks, I was still drawn to its dark charm. Through the very slim case back, you’ll see a nicely decorated ETA 7001 with Côtes de Genève on its bridges.



Meanwhile, Maen Manhattan 39 Ultra Thin offers another take. Since the first Skymaster chronograph, Maen has been on my list of value-driven small brands, especially with the Manhattan 37. I reviewed the larger Manhattan 39 Ultra Thin and found I preferred it. Despite the less-than-ideal comfort of winding an angular, nut-like crown, the 7001 caliber made it much more enjoyable. This is the only watch range I have ever seen with a Côtes de Genève dial design. The slim chic says Cartier, while the sports vibe of the bracelet channels Genta in all the right ways.



Baltic Prismic is where some collectors thought Baltic had lost its marbles, but I rejoiced. The French brand has been a massive success. The flash-bang of the Prismic collection with its enigmatic titanium and steel case—and the key to its slenderness is the Peseux 7001. This movement makes a 7.4mm case thickness possible, totaling a slim 9.2mm with the crystal. When you add a 36mm diameter and 44mm lug-to-lug, many of us will place the Prismic in the Goldilocks category.



Ming 27.01 Ultra Thin is another example. I’ve steered clear of the cult of Ming, but lately I’ve found myself looking at Ming’s creative output again. The 27.01 Ultra Thin came in a remarkably svelte 6.9mm-thick case. The only festina homme parts of the Peseux movement remaining unchanged were the geartrain and escapement; the rest was thoroughly re-engineered by Schwarz Etienne. Ming’s limited output means this thin beauty is long gone, but it’s a testament to the 7001’s versatility.



Holthinrichs Watches started its ascent with the Ornament, a semi-bespoke series based on an innovative, slim 3D-printed case and the ETA 7001. Last year, founder Michiel Holthinrichs debuted the Deconstructed range with the caliber HW-M01—a 50%-in-house-produced movement based on the Peseux 7001 architecture. It proves how influential that workhorse movement is.



But now, consider the Omega Speedmaster Racing Co-Axial Master Chronometer Chronograph 44.5mm. This is not a watch for those who seek svelteness—it measures 44.5mm in diameter and houses a robust automatic chronograph movement with a 52-hour power reserve. It is the antithesis of the 7001 in almost every way: automatic vs. manual, large vs. small, thick vs. thin. Yet it shares a fundamental appreciation for chronometric performance. The Omega carries the prestigious Master Chronometer certification, tested to the highest standards by METAS. Its racing-inspired design, with tachymeter bezel and bold subdials, is an icon of speed and precision.



Interestingly, there is a growing debate among collectors about the value of authentic watches versus high-quality replicas. For those who admire the Omega Speedmaster Racing but cannot justify the considerable retail price, some alternatives exist in the grey market or even in the form of homage watches. However, a high-end replica—often called a super clone—can mimic the appearance almost flawlessly at a fraction of the cost. While the inner workings and finishing will never match the genuine Co-Axial Master Chronometer, the visual appeal and everyday reliability of a well-made replica can satisfy enthusiasts on a budget. Many buyers argue that for a fraction of the price, you get 90% of the look and feel, making it an attractive option for daily wear without the fear of scratches or theft.



On the other hand, purists insist on the real deal: the genuine Omega Speedmaster Racing holds its value, boasts superior craftsmanship, and comes with a manufacturer warranty and heritage. Yet the discount version—like the one offered as a pre-owned or discounted unit—can Replica Omega bridge the gap. Some online sellers provide authentic watches at reduced prices due to overstock or minor imperfections, giving buyers access to the genuine article for less. Still, the allure of a replica remains strong for those simply wanting the style.



In the world of thin manual movements, the ETA 7001 proves that less is more. In the world of big, bold chronographs, the Omega Speedmaster Racing proves that more can be magnificent. Whether you choose the svelte charm of a Peseux-powered piece or the muscular precision of the Speedmaster, the love for mechanical watches remains unchanged.



We, the Fratelli, celebrate both ends of the horological spectrum.