Monochrome Watches
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Review – Clerc Hydroscaph GMT Power Reserve Chronometer, the heavy diver

| By Robin Nooy | 11 min read |
Clerc Hydroscaph GMT Power Reserve Chronometer

The choice for dive watches is quite literally endless. There are thousands of good, very good, or extremely good dive watches out there. There are also plenty of so-so dive watches, so it is very possible to lose track of what’s what in this popular category. Thus, we feel it is our duty to share some options outside the beaten path of Submariners, Seamasters or Panerais. One of these options is Clerc, a brand dedicated to dive watches with a bold design. Today, we bring you the Clerc Hydroscaph GMT Power Reserve Chronometer, first introduced last year, in one of our extensive reviews, including specs, lots of pictures and of course, our personal thoughts!

A dive watch is not only popular amongst actual divers. Most are very rugged, usable tool-watches but a lot of them never go near their depth ratings. Nevertheless, most of them see water in one way or another (shower, swimming pool, heavy rain) so it is a comforting thought that your precious watch is able to take a bit of a beating. And a beating a Clerc can take, we have to grant them that!

Clerc Hydroscaph GMT Power Reserve Chronometer

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Overall appearance & features

In one word: BIG. In another word: SOLID. That is the most common feedback I got from people while wearing either the black or the steel version (or both at times, I am a watch-nerd after all). It becomes clear when handling the watch this is no subtlety, not in design and not in construction. And to be honest, I can really appreciate a big, bulky watch, as I can appreciate very slim, elegant watches. Even though this is not for everyone’s liking, taste is still a matter of opinion. Luckily, Clerc has put a lot of attention to detail in these watches. The legibility is very good, the lume is strong, the bezel aligns perfectly and rotates easily after unlocking. Speaking about the bezel, the unique unlocking system is a bit fiddly at first but works surprisingly well, more on that later on.

Clerc Hydroscaph GMT Power Reserve Chronometer

As the name of the watch suggest, quite a long one by the way, it features a chronometer certified, automatic movement with a GMT and Power Reserve functionality. Other than that, it has a diving bezel with large numerals, a date indication and a cool 3d-like dial. Not 3d in the sense it is an animated one or whatever, but a dial that has a lot of depth.

Dial and hands

Speaking of the dial, there are multiple colors available in the Clerc Hydroscaph GMT Power Reserve Chronometer collection, besides the black and silver one you see here. You can also opt for blue, or brown, so 4 colors in total. Depending on the choice of color, choice of strap or bracelet or choice of treatment for the case you get very different watches.

Clerc Hydroscaph GMT Power Reserve Chronometer

The dial of the Clerc Hydroscaph GMT Power Reserve Chronometer is bold, as is the entire watch. Large applied numerals and markers for the hours with equally large hands for hour and minutes. The hour markers are facetted and come in various combinations; polished with black filling, polished with white filling, black with white filling or rose gold with white filling, all depending of color of the case and dial. A black case receives black markers, a brown dial gets rose gold markers, you get the idea.

Clerc Hydroscaph GMT Power Reserve Chronometer

The dial also displays the date, which cuts into the numeral at 3 o’clock. The date disc underneath always has the same color combination (white number on black disc) which is fine for most watches but it somehow gets a bit lost on a black dial. At least, something is a bit subtle in here.

The large hands are helpful when you’re in dark or challenging circumstances, and they allow you to tell time a quick glance. The hands have a decent length and are very wide. The first part, near the central stem, is opened up to show the dial underneath, the second part is filled to match the hour markers, so either white or black. The subdial at the bottom of the dial is a display for the GMT function which has a mother of pearl inlay. A nice, elegant detail of an otherwise bold statement of a watch. The subdial is fitted with a black hand, with yellow or white tip and can be adjusted by the little pusher at 4 o’clock.

Clerc Hydroscaph GMT Power Reserve Chronometer

At the very top of the dial you will find a large triangular marker which allows you to realign the bezel after your dive, and underneath, the Power Reserve indication. The remaining power stored in the barrel is indicated by another small black hand with yet again a white or yellow tip. The hand moves along a curved fuel-gauge like scale

This 3d layout of the dial and hands results in a design that really changes when looking at it from various angles. The light plays with the hour markers, the recessed mother of pearl subdial for the GMT indication too, so there is a lot going on when wearing this watch. You might consider it busy, but I will contest that to say it is designed and built with legibility in mind so markers and such are oversized for a reason.


Clerc Hydroscaph GMT Power Reserve Chronometer

This is the biggest (pun intended) visible feature of the watch. In some timepieces it is a moonphase, a skeletonized movement or a tourbillon, but here it’s most definitely the case, no doubt about that. The case measures a whopping 48mm wide, due to the peripheral case protection, something that is a trademark by Clerc. All of their watches feature this robust protective band around the inner case, whether it is the H1 Chronometer, Central Chronograph or this GMT Power Reserve Chronometer.

Clerc Hydroscaph GMT Power Reserve Chronometer

The 48mm wide steel case, 43.80mm at the edge of the bezel so without the peripheral case guard, is available in bare steel, PVD or PVD with rose gold bezel. The entire watch, steel case, bezel, sapphire crystal and all, is 15mm thick so it sits well on top of your wrist. This is not a subtle watch, that much is obvious by now, but it also doesn’t want to be. It doesn’t want to fit under a cuff, or match with a tailored suit. No, this watch is to be seen, to be out there in the most outspoken manner possible, while still maintaining a purpose as a diving tool. And a diving tool it really is, as it is water resistant to 800 meters, due to the helium escape valve positioned at 9. Some will argue that the extra hole for the helium escape valve infringes water resistance, and considering this also has a hole for the GMT-pusher, 800 meters is still impressive stuff. Far beyond where you and I will ever end up taking a watch like this.

Clerc Hydroscaph GMT Power Reserve Chronometer

Surrounding the case, there are several protrusions to operate the various functions of the watch. The smallest of these is the little pusher for the GMT at 4 o’clock and it seems a little lost compared to the others. Above that, is the screw-down crown featuring the double “C” logo. On the other side of the case is the helium escape valve (not really something that sticks out in the literal sense) to release excess pressure if needed, and it is accompanied by the bezel locking crown at 10 o’clock. This has a flip-up C-style part that can be used to rotate the bezel. If it is folded down, the bezel is locked in place and will not move. If flipped up, you can turn it (or grab the bezel, a lot easier) to rotate the bezel and time your dive. If you grab the bezel like on a traditional diver’s watch by the way, the bezel locking crown rotates along with it.

Clerc Hydroscaph GMT Power Reserve Chronometer

Depending on what version you have, and if fitted on a rubber strap or steel bracelet the watch weighs either 180 grams or 240 grams which is simply put; a LOT. Compare this to, oh let’s say, the aforementioned Ressence Type 5 which comes in at 87 grams, you get an idea of the weight of this watch. The case does feel very good on the wrist however. The sharply angled lugs, neatly hinged so they can swivel, keep it tightly secured to your wrist. This means that despite the size and weight, it doesn’t move around much when wearing it. And that, in all fairness, is a really good thing. Nothing worse than a large, top-heavy slab of watch on your wrist which moves around uncomfortably!


The movement powering this Clerc Hydroscaph GMT Power Reserve Chronometer is Clerc’s C610 automatic movement, partially visible through the sapphire caseback. This see-through window doesn’t cover the entire caseback, but rather provides a partial view of one the most important visual bits: the rotor at work and balance wheel swinging back and forth.

Clerc Hydroscaph GMT Power Reserve Chronometer

The automatic movement also features a dual-time function and a power reserve. Besides that, it also indicates the date at 3 o’clock so it does quite a bit here. The C610 beats at a frequency of 28,800 bph and can store a total of 42 hours of power. It is also an official COSC specified movement, so it operates within a range of -4 to +6 seconds of deviation a day. The movement is most likely based on an Soprod C-115, an ETA-clone with a module on top for the various complications.

A smaller, second window opens up even more of the caseback and features a printed double “C” logo like on the crown.

Strap and buckle

The Clerc Hydroscaph GMT Power Reserve Chronometer comes on a one of two available of straps or a bracelet. The straps are in black, brown or blue rubber, either with straight lines or with an alligator-leather finish. The bracelet is a full link type bracelet, only available in steel and not a PVD coated version. The rubber used for both the striped strap and the alligator patterned one are very comfortable, soft and with a slightly vanilla scent that helps to really experience your watch to the fullest.

Clerc Hydroscaph GMT Power Reserve Chronometer

The strap is supple enough to move with your own movement during the day, but also sturdy enough to keep it in place and not flex too much while wearing the watch. Attached to a quite large, but flat folding buckle with a deep engraving of the brand’s name across it, it follows the (with all due respect of course) big-and-bulky theme.

Clerc Hydroscaph GMT Power Reserve Chronometer

The strap is attached to the case between articulating lugs that aid the comfort of the watch on the wrist. The movement of these swivel lugs isn’t much but it really helps, it just makes that little of a difference that enhances the experience of owning and wearing such a watch.


The Clerc Hydroscaph GMT Power Reserve Chronometer is a hefty watch, one that you really feel when wearing. It has big weight, big presence (in steel or PVD, it doesn’t matter one bit) and big features making this an impressive watch to wear. It grabs attention from just about anyone, really. But does that make it a watch to consider? Well, that is always up to you but I strongly feel this needs something like titanium for the case in order to make it a bit more wearable for the vast majority of the people. Clerc does offer other, lightweight materials such as carbon so it could be a thing of the future.

Clerc Hydroscaph GMT Power Reserve Chronometer

On the other hand, this watch is built to look and feel virtually bomb-proof and the construction is very solid. The case is protected by the peripheral case guards and it remains highly legible in various conditions. Not as much as a Ressence Type 5, but I felt that it lived up to the task of being a rugged, strong diver’s watch in a big way. So if you can take (or want) a bit of heft, this is something for you! A final thing that should be said about the Clerc Hydroscaph GMT Power Reserve Chronometer is that I feel it is executed along a certain theme, and they paid attention to most of the important details to make it a proper dive watch.


  • Very solid build, extremely durable feel.
  • Recognizable, stand-out design.
  • Legibility is very good.
  • All the merits of a proper diving tool.


  • BIG: big weight, big height, big diameter.
  • Design that is not for everyone
  • Price compared to industry rivals and icons
  • GMT button seems a little lost in execution next to crown and bezel lock

Clerc Hydroscaph GMT Power Reserve Chronometer

Specifications of the Clerc Hydroscaph GMT Power Reserve Chronometer

  • Movement: Mechanical self-winding, C610 calibre 31 jewels, 28,800 bph, 42-hour power reserve
  • Functions: Hours, minutes, central seconds, date, power-reserve indicator and 24-hour dual-time display
  • Case: Steel or Black DLC-coated high-density steel or 18K red gold and black DLC-coated high-density steel – 43.8 or 48 mm with lateral reinforcements – Crown activating and locking the rotating bezel – Glare proofed sapphire crystal on both sides, dual-porthole exhibition case-back – Automatic helium release valve – 83 components – Water-resistant to 800 m (80 ATM/2,624 ft)
  • Dial: White, brown, midnight blue or black Central hours, minutes and seconds hands Date aperture at 3 o’clock – Power-reserve indicator at 12 o’clock 24-hour dual-time display at 6 o’clock
  • Strap: Vulcanized rubber or alligator-finish rubber with folding clasp
  • Price: USD 7,850

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