Sinn EZM 10 Review

The world of pilot’s watches is a crowded one, with seemingly a new model, line or brand dedicated to the style coming out every day. But not all are created equal, and not all are made to truly be worn by pilots. Naturally, most of us are not pilots, myself included, and don’t need something that is truly to spec, but often the same technologies and details that make them fit to fly also just make them long-lasting, tough-as-nails tool watches with bold and aggressive designs. Of the few brands that offer something truly meant for the cockpit, Sinn’s watches go the furthest, offering the most cutting-edge tech as well as TESTAF certification, authenticating their credibility.

We’ve looked at many a Sinn before on w&w, from the classically styled pilot’s chronos 103 and 356 to the clean and purposeful 556i and 240 to the mission-ready EZM 13 diver’s chronograph, all of which offer a great value for their build quality, style and functionality. Today, we’re going to take a look at a watch that sits at the top of Sinn’s food-chain, the EZM 10. Packing more technologies than most brands will ever develop, a unique modern design, an in-house modified 7750 that recreates the function of the Lemania 5100 and TESTAF certification, the EZM 10 is quite possibly the most serious pilot’s chronograph on the market.

Of course, all of those features come with a cost, making the EZM 10 at $5,290 one of Sinn’s most expensive pieces. That said, compared to luxury brand offerings at the same price, or frankly double and triple that price, the EZM 10 stands alone with its feature set. Like all Sinn’s, it offers a unique value, one that is based on an honest though not cheap price for something high-end and unique. With the EZM 10, you also have a watch that is very specific and designed as an instrument, and while useable as an everyday watch, likely will appeal to die-hard pilot and chronograph fans, as well as people who need the level of tech inside. And for those people, there really is nothing else quite like it.

Case

The EZM 10 case is big and bad, with a unique modern design, making it standout within Sinn’s lines. Measuring 46 x 52 x 15.75mm, it’s a pilot’s watch in the original sense of the term. A big bold design that is meant to be read at a glance, and potentially under adverse situations. This does however make it limiting for those who prefer smaller watches or simply can’t pull off a 46mm. To temper the size, Sinn went with titanium for the case, decreasing its potential weight. Well, not any titanium, Tegimented titanium. This is the first, and perhaps most useful on daily terms, tech you’ll encounter on the EZM 10. Tegimenting is Sinn’s proprietary case hardening method, making the watch near impervious to scratches.

Looking at the design and geometry of the EZM 10, it’s far more contemporary and aggressive than Sinn’s staple chronographs like the 103 or 356, which have cases that could or do date back to the mid-twentieth century. From above, it appears to be a bit of a lugged-barrel, with wide, strong lugs. Two design details that are immediately of note are the chunky bezel and unique pushers. Rather than the thinner and more subtle bezels occasionally found on pilots watches, Sinn went with a tall, wide toothed design. Combined with the broad case, it is slightly reminiscent of the gen 3 Heuer Autavia design. Obviously, the design is meant to be easily manipulated in normal and harsh conditions.

The bezel has a 60-click bi-directional mechanism with a very solid and satisfying feel. In a slightly unusual move for Sinn, the bezel insert on the EZM 10 is sapphire, which makes it very scratch resistant, though does add some reflections/glare depending on the light. The bezel also features Sinn’s “captive” design, which attaches the bezel to the case in a non-standard fashion, preventing it from being lost should the bezel endure a sharp blow.

Moving to the right side of the case, you have the EZM 10’s unique low-profile pushers, and a large screw-down crown. The pushers are a standout feature of the watch. Likely drawing from the famous Tutima NATO chronograph, the low-profile pushers prevent any potential snagging that traditional pushers might pose. They also look really sleek. They are nearly flush to the case, but step out just a bit, maybe a millimeter, and then feature beveled edges. Making them stand out in the subtlest of ways, they are PVD coated, which adds to the overall aggressive feeling of the watch. Since they are so wide and flat, depressing them is easy and satisfying. It’s worth nothing that despite the non-traditional pusher design, the EZM 10 still has a 200m depth rating.

On the bottom left lug, you’ll find another signature Sinn technology, a copper sulphate capsule, which is part of their 3-part Ar-dehumidifying system. The copper sulphate absorbs any moisture that might get into the case, and “binds it permanently”. As it pulls more and more moisture from within the case, the white dot that is visible will turn blue (over several years). Once blue, it must be replaced to keep functioning properly. The next part of the system is an inert gas filling to the case. By replacing the air inside of the case with gas, they further eliminate the presence of any moisture, which in turn leads to  a longer lasting watch, as well as prevents fogging. The last part of the system is the use of Sinn’s  Extreme Diffusion-Reducing (EDR)-seals, which greatly reduce moisture infiltration over conventional seals. Do you “need” this level of dehumidifying tech in your watch? For daily use, unlikely, but the point is that the watch can survive way beyond the usual.

As one would expect from a watch focused on durability, the EZM 10 has a solid caseback, also titanium. There are a handful of details etched or stamped in, with one worthy of note. Dead center, under the name of the watch, you’ll find an icon of a plane on approach with small t-like marking above and below it. This is the official TESTAF certified logo, which also appears on the dial.

Dial

Finally moving on to the dial of the EZM-10, you’re presented with a clean and bold design indicative of Sinn’s EZM (Einsatzzeitmesser) watches. In fact, if you take a look at the EZM 13 we reviewed a few months ago, you’ll see that while the dials are totally different, they use the same vocabulary of markers. The goal here is clarity and legibility, both of which Sinn is pretty darn good at. The primary index consists of large lumed rectangles, doubling and tapering slightly at 12. Between these markers are thinner white lines for the minutes/chronograph seconds, and then, with a smaller diameter, is a ring of smaller marks for 1/4th seconds. It’s busy and intense, but still very readable at glance.

Stepping in, you have three sub-dials, which is where things begin to get very interesting. As mentioned briefly in the intro, the EZM 10 is powered by a modified 7750 called the SZ01. The goal of the SZ01 is to have the functionality of the retired Lemania 5100 movement, namely by having a centrally mounted minute counter for the chronograph. Additionally, it features a 24-hr sub-dial, which is located at 3 on the EZM 10. This actually differs from the 5100, where it would have been at 12. Frankly, I think the layout of the SZ01 is an improvement as it provides a more balanced design.

Back to the sub-dials, at 6 is a twelve hour counter and at 9 is the active seconds. The execution of the sub-dials is very simple, they are all flat printed on the dial, no indentations of textures to speak of. To make them stand out a bit, they circled the 24-hr and active seconds with gloss black lines. They also color-coded them, making time functions white, and chrono functions day-glow orange. This once again plays off of the balanced layout as the white subs are left and right, while the orange sub is center. Each sub-dial features large, almost oversized, numerals at their respective quarters.

Stepping out to the bezel, you have a white on black countdown index under the sapphire insert. It features numerals every 5 minutes/seconds on top of rectangles, with small lines for the individual minutes/seconds and a large triangle at 0/60. All feature very potent lume. Aesthetically, it works well with the dial, extending it out to the edge of the case for a lot of visual impact. To use the bezel, you line the amount of time you wish to countdown from up with the chrono minutes/seconds or time minutes, and then wait for it to reach the 0 triangle.

Functionally, I’m not sure how much I like having a countdown index over a classic index or dual time. At a glance, it can be a bit confusing as the numbers are flipped… so at 10 you have 50, at 45 you have 15, and so on. Obviously, commonsense overrides the confusion quickly, but it can still be a bit jarring, like looking at the word red written in blue. Additionally, and I’m obviously saying this as a non-pilot, but countdown timers aren’t something I need on a regular basis, thus it will end up an unused element. Dual time, how ever, comes in handy often, especially if you travel with some frequency.

On the dial, you have a few works and markings. Below twelve is the classic Sinn logo with EZM 10 written underneath in a more modern typeface. Just above 6, you have “made in Germany” and then just below the central axis, you have the word “DIAPAL”, which is often obscured by the hands. This indicates the movement features Sinn’s DIAPAL technology, which we’ll get into in the movement section below. Between 7 and 8, in dark gray, you have the same TESTAF symbol found on the case back. The execution here is nice, as the dark gray makes it easy to ignore if you are just looking for the time at a glance. Lastly, you have a date window between 4 and 5 with white numerals on a black surface. This works with the dial as well, balancing the TESTAF logo, and not drawing too much attention. My only qualm is that I wish they could have corrected the angle of the date, like they do on the 556a.

The hands of the EZM 10 are true to Sinn’s style. The hour and minute are straight swords with edge to edge lume that get the job done efficiently. The chronograph seconds is a tapering stick in orange and white, with the latter lumed, making it really jump off of the matte black below. The chrono minutes hand mimics the seconds, but adds two angled wings, making it easy to distinguish from the seconds. This also refers to the handsets found on older Lemania 5100 watches, whether from Sinn or other brands. The sub-dials each feature small stick hands in white or orange depending on the counter’s function. With a total of 7 hands, you’d think the EZM 10 would be confusing to use when the chrono is running, but it’s not all thanks to the well thought out hand designs.

Movement

The Lemania 5100 is a movement of such high regard that we gave it its own article. The 5100 was used by Sinn in many watches in the 80’s through the early 2000’s, from the 140/142 that went to space, to the mil-spec EZM 1s that kicked off their Mission Timer series, to my personal favorite, the 156, which was design to be a follow up to the Heuer Bund. The unfortunate demise of the 5100 left Sinn and various other brands without a comparable replacement, either dropping those watches from their lines, or using 7750’s in their stead. While the 7750 is a high-quality workhorse, it lacks the centrally mounted chronograph minutes that make the 5100 so easy to read and use. There are many other differences as well, namely a completely and utterly unique architecture that made the 5100 incredibly durable and able to withstand high Gs and shock, but forgetting that for a second…

With this hole in the market, Sinn developed their own replacement in the SZ01, which is a heavily modified Valjoux 7750. The goal was to recreate the functionality of the 5100, by adding the centrally mounted minutes as well as the, granted less important, 24-hour sub-dial. As noted, the 24-hr sub went from 12 to 3, and improvement in my eyes. Because it’s based on the 7750 you can expect some similar specs: automatic, 25-jewels, 42-hour reserve, hacking, hand winding, date (no day), and a frequency of 28,800 bph. They then added in the central minutes and 24hr display. I can’t stress how useful the central minutes is enough. First off, it counts a full 60-minutes, which In my opinion, all chronographs should do, but by being centrally mounted, it’s also really easy to read at a glance. Imagine if your being rattled around in a cockpit and you need to check the chronograph (not sure why that would happen, but moving on…) do you really think you’ll be able to focus in on a tiny sub-register to count the exact minutes?

In addition to the added functionality, Sinn used their DIAPAL technology in the SZ01 featured in the EZM 10 (note that they do not use DIAPAL in the 140). DIAPAL is a lubrication-free escapement system that with the Ar-dehumidifying tech of the case, creates a longer lasting and more accurate movement. In a standard movement, their is lubrication on the ruby/pallet stones in the anchor escapement. Sinn initially wanted to replace the rubies with diamonds, hence the name DIA-PAL, but that didn’t get the desired result. The materials used in the current system are unnamed and likely proprietary, but they achieve the lubrication and friction free escapement results Sinn sought. Yet another unique and value adding tech to add to the list for the EZM 10.

Strap and Wearability

The EZM 10 comes mounted to a 22mm Di-Modell Chronissimo strap. If there ever was a leather strap that was built to the same standards as the EZM 10, this is it. These straps are rugged, impervious and over built featuring various layers of padding, heavy duty double stitching, notched design by the lugs and waterproof leather and construction. They are very thick, measuring nearly 7mm at the lugs, but taper down for comfort. It really is the logical choice for the EZM 10, though a Bund strap would be cool too. The one thing I could do without is the orange highlight stitch, as it’s a bit too much color for me. I get that it brings out the orange in the dial, but all black would have been my preference.

On the wrist, the EZM 10 wears like the big chronograph it is. 46 x 52mm are not subtle dimensions no matter how you look at them. With that said, the watch was still wearable and comfortable, likely because of the titanium. On my wrist, which is 7″, it definitely looked a bit oversized, especially in the lug-to-lug, but didn’t look absurd either. It’s one of those watches that is so cool looking and fun, that you kind of get past the fact that it’s big. It also doesn’t look like a watch that is big to follow a trend, rather it’s big to be more legible and functional. It’s an instrument more than a watch.

Aesthetically, the EZM 10 an intense watch with a look all to itself. It definitely has Sinn DNA though and through, but is actually more aggressive and modern than most of their other pilots watches. The use the dark titanium case and black pushers give it a sleeker look, while the bright orange and chunky bezel add to its fierce attitude. In terms of styling, I mean, it’s not a dress, that’s for sure. I definitely felt like it looked most appropriate with rugged attire.

Conclusion

The Sinn EZM 10 represents the top of Sinn’s pilot line of watches and proves what the brand can do. When you consider the feature list: tegimented titanium, Ar-dehumidfying, DIAPAL escapement, in-house modified 7750 with unique function and TESTAF certification, you realize that Sinn is in a class of their own. Sure, there are plenty of other pilots watch brands out there, some also offer tech while others hide behind the veil of “luxury”, but none have a feature set like the EZM 10. The SZ01 movement alone is enough to make this watch a winner. Add to that that is simply doesn’t look like any other watch out there, and you really have a really outstanding watch.

Sure, at $5,290, it’s also expensive, but the price is warranted and it’s still a good value for what you are getting. Most $5k pilot’s watches cost that much because they have to pay for sponsors and tacky marketing campaigns, not for what they actually do. Here, the reasons for the price are obvious. I also don’t think Sinn intends for this to be a watch for everyone. It’s going to have a self-selective audience, who want or need something like the EZM 10 and know what they are willing to spend for such a piece. So, if you’re a die-hard Sinn collector, a chronograph/Lemania 5100 obsessive, a pilot watch enthusiast, or an actual pilot, the EZM 10 should certainly be on your radar.