With this review, Mk II will be making its very first appearance on Fratello. However, it is a brand known to those who are into historically accurate, modern-made military dive watches. There are many military watches, vintage and new, that watch collectors are into, and the Mk II Stingray II Keroman has become a sought-after timepiece. Let’s find out why! 

Mk II’s founder Bill Yao developed a few collections that he has meticulously put together over time. His goal has always been to make the best watches money could buy and that would look and feel like the real deal. Or, to be more accurate, the goal was to make robust tool watches that only cost what they should. According to the brand’s website, “Mk II exists to re-imagine inspirational ideas, designs, and concepts from the past.” One such inspiration is the Blancpain mil-spec dive watches that, under the name Tornek-Rayville, became the go-to timepieces for the US Navy in Vietnam. Today, some people are very much into these watches as they represent the quintessential, capable military diver. The Mk II Stingray II Keroman is a watch for them, so if you love those watches too, read on.

Mk II Stingray II Keroman

The heritage that weighs on the lugs of the MK II Stingray II Keroman 

While the name “Stingray” is pretty much self-explanatory, what does “Keroman” refer to? Well, Keroman is the name of a tiny peninsula outside the city of Lorient on the west coast of France. It is where, during World War II, the Germans hid a heavily fortified submarine pen. The latter was then repurposed by the French Marine Nationale after the war. Here lies already a clear connection to the military and especially the navy. As mentioned above, the US Navy bought Tornek-Rayville divers to be used during the Vietnam War. Because the lume on these was made of radioactive material, most watches were destroyed at the end of their service. Those that weren’t are now highly collectible. 

One of the elements that made the Tornek so popular was its utilitarian-looking and well-proportioned case. The modern Mk II truly looks like a piece of military equipment when looking at the perfectly flush bezel and sandblasted finish. It is these intrinsic military qualities that brought the fascinated Bill Yao to re-create this iconic type of military diver. Just like the 1953 Blancpain Fifty Fathoms was built to spec for the French underwater commandos, 20 years later, the US Navy needed its own version of a robust diver. In other words, the OG which inspired the Stingray II was a quintessential piece of military equipment. And as such, it was built to withstand the most extreme conditions. How robust was it? Well, let’s take a closer look at the specs of Bill’s version to get a good sense of it. 

Mk II Stingray II Keroman

Built like a tank

To fit modern wrists, the Mk II Stingray II Keroman was slimmed down. It has a case diameter of 40mm (down from 42mm), a length of 48.5mm, a thickness of 14.7mm, and a lug spacing of 20mm. It sits well on my 16cm (6.25”) wrist given the long and thin lugs à la 1970s Fifty Fathoms models. “Robust” doesn’t have to be synonymous with “enormous,” however, and that is what Bill aimed for here. The goal was to build a modern re-creation of this type of watch to fit today’s watch enthusiasts’ preferences. The “built like a tank” aspect of the Stingray can be explained by looking at three aspects of its construction. 

First, the bead-blasted finish on the case means the watch does not mind scratches. I believe it also ever so slightly reduces the impact of shocks, but you shouldn’t quote me on that. Second, the bezel insert is made of aluminum, which is more solid than ceramic or acrylic. The aluminum also has a matte finish, which reinforces the utilitarian aspect of the Stingray II. (Note: this model is also available with a vintage-inspired acrylic bezel insert.) Third, the watch is provided on a heavy-duty single-pass fabric strap complete with beefy 2.50mm spring bars. I don’t know about you, but it seems to me like Bill wants us to be ready for the next apocalyptic-level event. 

Mk II Stingray II Keroman

True utilitarian design 

I always mean well when I use the word “utilitarian” in a review. I’ve handled many tool watches in the past three years. But rarely, if ever, have I gotten my hands on a watch that reaches this level of purposefulness. And this shows through in many ways. For example, the textured matte dial absorbs light and echoes the finish on the bezel insert. The white hour markers and hands contrast superbly with the dial, making reading the time a breeze. Likewise, the silver markings on the bezel insert stand out from the black aluminum background. Although a date at four-thirty can divide the watch community, here, it doesn’t break the symmetry. I also happen to like the addition of a date on a tool watch. 

If you are super nerdy like me, the way a bezel “clicks” can be a deal-breaker…or a deal-maker. The bezel action on the Stingray II Keroman is smooth and precise. It’s akin to that of a high-end Seiko diver and close to that of a Serica 5303 if you know how that feels. So you have a solid bezel that turns smoothly and aligns, something that not all low-to-mid-range Japanese dive watches can claim. Furthermore, the large and grippy crown is recessed into the case, protecting it against accidental shocks. Doing so eliminates the need to add crown guards which would have made the case less symmetrical.

I know, all of this only shows that the Stingray II Keroman is 100% a tool watch and won’t be everybody’s cup of tea. However, we can agree that it could easily equip the US Navy SEALs, right? 

Mk II Stingray II Keroman

Specs that complete the Stingray II Keroman 

Indeed, this review is getting long, and you must be anxious to know the rest of the specs. So here you go: the crystal is a double-domed piece of sapphire with an inner AR coating. The lume is Super-LumiNova which looks white during the day and glows green at night. Inside the case is the lesser-known Seiko NE15C, which beats at 21,600vph (3Hz) and provides a 50-hour power reserve. The NE15 comes with an ETA regulator, and although I’m no expert, it seemed important to mention it. Lastly, the Stingray II Keroman features a 200m water resistance rating. Mk II tests its watches according to the ISO 6425 requirements, however, the watch is not officially ISO 6425 certified. 

Mk II Stingray II Keroman

Final thoughts 

While Bill’s niche is to re-create iconic military watches, mine is to find people who re-create iconic tool watches, hence this review. People like Bill spend time looking for watches that had a purpose and that he can remake for us today. It’s not only about the design but also about the ethos of this type of watch, why it was created, by whom, and for whom. In my humble opinion (and please share yours below), the Stingray II Keroman looks like a proper military watch. It’s as if Bill time-traveled to make the original better. My argument might be a little far-fetched, but I think you can catch my drift. 

Mk II Stingray II Keroman

If you are interested in the Mk II Stingray II Keroman, you should know that the brand will restock in mid-June. The version with the aluminum bezel retails for US$895, and the version with the acrylic bezel sells for US$940. You can learn more about the Stingray II by checking out the Mk II website.

Watch specifications

Stingray II Keroman
Matte black with painted Super-LumiNova indices
Case Material
Sandblasted stainless steel with aluminum bezel insert (acrylic bezel insert also available)
Case Dimensions
40mm × 48.5mm ×14.7mm
Double-domed sapphire with underside AR coating
Case Back
Solid stainless steel, screw-down
Seiko NE15C — automatic winding, 21,600vph frequency, 50-hour power reserve, quick-set date
Water Resistance
Nytex single-pass strap (20mm width)
Time (hours, minutes, central seconds), date, 60-minute dive bezel
US$895 (aluminum bezel insert) / US$940 (acrylic bezel insert)