Hands-On: Underwater With The Synchron Military Poseidon

The calming rhythm of the Pacific Ocean gently lapping at rocks is broken by the harsh cry of seagulls. A young boy is eating ice cream, his father watching in amazement as two freedivers emerge from the swell, carrying extra-long flippers and wearing massive snorkels. The pair look rather like sea monsters until they pull off the snorkels. The young boy immediately loses interest. I glance down at my wrist and see the seconds hand of the Synchron Military Poseidon sweeping around the dial.

As this scene unfolds, I am preparing my underwater 35mm film camera. I review my internal checklist — look over the camera for sand and grit that might compromise waterproofness, check the seals and gaskets, and make sure the lens is on correctly and tightly sealed. I take the camera, a Nikonos-V, and plunge in. Immediately swallowed by the ocean, the shock of temperature change forces me to exhale sharply.

Another dive watch?

I look down at my watch again and set the timing bezel to the oversized yellow minute hand. I’ve got 40 minutes to shoot through a 36-shot roll of black and white film. The eggshell-colored dial and cream-colored indices are easy to see underwater. I’m testing a new watch, both a new release and a new acquisition, the Synchron Military Poseidon.

Dive watches… I have always had a soft spot for them. My first-ever watch purchase, a vintage Seiko 7002, is now in the possession of a good friend of mine since I gave it to him for his 30th birthday. It still goes strong after service, and it spends plenty of time in and out of the water. As someone who is in the ocean every day, I’ve always gravitated to the rugged design aesthetics and mission purpose of dive watches. 

So it could be a consistent formula, and some could even call it boring when I admit that what pulls my horological heartstrings is likely going to be a three-handed dive watch with a timing bezel. Yet the Synchron Military Poseidon is an intriguing dive watch that manages to upend this formula a bit and retain the magic of that rugged, purpose-built vibe.

An unusual design

When the Synchron Military came out in 2021, its unusual design sparked some controversy. The Military was a clear homage to the Doxa Army, an obscure watch from the 1970s that was designed for Swiss military divers. Its unique dial design made it a sought-after and incredibly rare watch for Doxa collectors. As my Fratello colleague Mike noted, the controversy came because Rick Marei, the current owner of Synchron, used to work with Doxa. Synchron actually owned the Doxa name back in the 1970s. Doxa has since reissued its own version of the Army.

The story of the Synchron Military Poseidon goes that Poseidon Diving Systems was asked by the Swedes to provide a tough mechanical dive watch. So, like the Tudor Pelagos FXD with its connection to an elite Marine Nationale diving unit, the Poseidon is a watch that also has military credentials. The Swedish Armed Forces used the watch for a COLDDIVEX exercise in Boden, Sweden. The exercise involved testing dive equipment in subarctic conditions, including temperatures of -30° Celsius. This explains the cool Poseidon logo on the watch’s dial. However, the civilian version is supposed to have some minor differences from the actual watches provided to the Swedes.

The Synchron Military Poseidon gets wet

The Pacific Ocean here in Sydney is somewhat warmer than the icy waters off Sweden. Nevertheless, the principle of using a tough and capable timepiece in rough seas is the same. So taking the Poseidon out to baptize the watch in its first-ever underwater expedition is a good way to get a sense of how this unusual-looking piece handles underwater legibility.

The light gray dial is easy enough to read underwater. Because it isn’t a bright white, it somehow doesn’t pick up sunny reflections as much (a good thing). The oversized yellow plongeur minute hand is easier to read than the bright orange minute hand on my Doxa Sub 600T Pacific. The bezel is grippy and precise, though it lacks some of the sheer solidity of the Doxa or, particularly, my Tudor Black Bay Fifty-Eight (both of these watches retail for considerably more than the limited-edition Synchron did upon its release). One thing that does look a little strange is the steel bezel rim, which seems to be blasted even though the case is brushed. This is also true of the standard Synchron Military, and it has been noted elsewhere too. Chalk it up to quirkiness, I guess. 

Dimensions and specs

The hefty 42mm × 45mm case wears reasonably well for my slim 6.15″ (15.6cm) wrist. The watch feels chunky at 14mm thick, but as a diving watch with Doxa design cues, I kind of like this aspect. A detail that I enjoy out of the water is the font on the date wheel. It’s definitely not a standard font, and it adds another slight level of quirkiness to a watch that’s already very out there. Is it sans serif? Someone let me know in the comments. The crown action is reassuring and surpasses the experience I have had with Oris or Doxa watches at double the price. It wrests nicely on the case, though it pops out further than on Doxa cases where the crown sits a little more snuggly in the case flank.

The movement has been keeping good time thus far. It’s a La Joux-Perret G100 automatic caliber adjusted to four positions, and it features a healthy 68-hour power reserve. I’m excited to own a watch with an LJP movement as this is a first for me, and I look forward to getting a better sense of how this movement performs over time. 

Final thoughts

I look down at the timing bezel again, and my 40 minutes are almost up. It’s time to head back to shore. All in all, I really enjoy this quirky Synchron. It is my first purchase from a Rick Marei brand, and I will probably be taking it on another adventure soon. Stay tuned. 

What are your impressions of the now-sold-out Sychron Military Poseidon? And what would you like to know about this watch that I haven’t covered here? Please let me know in the comments. 

You can also find me on Instagram: @onhenryswrist