Monochrome Watches
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The Longines HydroConquest GMT, an (Almost) Perfect Traveller’s Dive Watch

Despite some very small complaints, the addition of a GMT function in the HydroConquest is a brilliant move by Longines!

| By Robin Nooy | 5 min read |

The long-standing HydroConquest collection of diving watches by Longines has been a fan favourite for years. Since its introduction in 2007, it gained significant traction with enthusiasts and collectors. It was presented as a more modern diving tool to offset the retro-styled Legend Diver, also (re)launched in 2007. During the course of its life so far, plenty of colour variations have been introduced, including two-tone models with gold PVD elements. The most significant expansion to the range, though, came earlier this year as Longines decided it was time to up the HydroConquest’s versatility. Incorporating True GMT functionality, the Longines HydroConquest GMT becomes a robust diving watch fit for a globetrotting lifestyle. So, with all this in mind and a hands-on experience being a touch overdue, we have finally spent some time with two of the four new HydroConquest GMTs.

With the introduction of the HydroConquest GMT also came a slightly new case design. The stout 41mm wide stainless steel case looks and feels very solid and is predominantly brushed, which makes perfect sense as it’s a tool watch at heart. The rotating diving bezel on top is polished to add a touch of contrast against the fully brushed case. The insert is polished ceramic in a colour that matches the dial, with a traditional 60-minute diving scale in white (blue or black dial) or beige (green or brown dial). The biggest change with this HydroConquest GMT compared to the non-GMT HydroConquest is the shape of the crown guards. Previously these were sharp and angular, whereas, in this one, they’re smoother and curve out of the caseband to meet the polished screw-down crown. With a water-resistance rating of 300 meters, you can throw pretty much everything you want to at it, and it will keep performing as it should.

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The dial of the Longines HydroConquest GMT comes in four different colours, and the brand has sent us the blue and green versions. All colours look equally handsome, although the green one is my personal favourite. The layout is simple but with a lot of attention to detail. It has a sunray-brushed finish, applied markers with Super-LumiNova and a printed minute track. Around the outside perimeter runs a 24-hour scale for the GMT indication. The central hour, minute and seconds hands contrast nicely against the coloured background and are finished with a spot of Super-LumiNova. My one complaint concerning the dial is the date wheel. Outlined at 3 o’clock, the green (and brown) dial comes with a colour-matched date wheel, whereas the blue (or black) dial has a white one. It would be nice if Longines would have colour-coordinated all models and not just two out of the four.

It’s almost a shame Longines hides the automatic calibre L844.5 under a solid caseback, as I love to see a good mechanical movement at work. On the other hand, it befits the robust and adventurous nature of the HydroConquest GMT. The movement is exclusive to Longines, so it should be seen as an in-house unit. It is one of the latest movements used by Longines, which is very similar to the one used on the Spirit Zulu Time. The caseback has a nicely done image of a globe, the brand’s name and the winged hourglass logo. Six notches allow for a watchmaker to unscrew it if needed.

In terms of performance, the movement runs at a rate of 25,200vph. It’s also fitted with a silicon hairspring and other anti-magnetic components to make it as reliable and robust as possible. The power reserve is well above average, at 72 hours in total. But the most important fact is that it’s constructed as a true GMT movement, which makes the local hour hand individually adjustable through the crown and not the GMT hand like in an Office GMT.

Longines fits the HydroConquest GMT on either a NATO-style strap for the green or brown dials, a black rubber strap for the black dial or a stainless steel bracelet for the blue. The bracelet is available for all models, by the way, and has a built-in quick-adjust system that gives you half a centimetre of play in length. It is a brilliant package overall, with just a few minor details to gripe over (which I will get to in a bit). It looks great, it feels amazing on the wrist, it delivers on the technical side of things, it’s a true traveller’s GMT watch, and the price isn’t too bad either. Sure, at EUR 2,950 on the NATO-style fabric strap or alternatively EUR 3,100 on the black rubber strap or steel bracelet, it costs a pretty penny, but I still consider it good value for money.

It’s not 100% smooth sailing though, as I do want to address some issues I have with not only this watch but with Longines in its current state as well. I already mentioned the date wheel not being matched to the dial on two of the four dial options. I also want to mention the folding clasp on the bracelet feels a touch on the sharp side here or there. This has not caused me any issues when wearing the watch, but you feel it when handling it off the wrist.

Let me just make one last personal comment. I would love to add this watch to my collection, and as we all know the bracelet is the way to go. The markup over a NATO-style strap is only marginal, so buying that one separately is usually the most sensible thing to do. But I have a hard time accepting that Longines asks EUR 195 for the fabric strap on its own. That’s a high price for what is basically a piece of textile with a steel pin buckle. Nevertheless, the HydroConquest GMT is, as a whole, an excellent watch.

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5 responses

  1. Imagine the price for a replacement strap for an Omega PO Ultra Deep Titanium, that sets you back 520 Euro in Germany. Granted, it is fitted with titanium elements, but…. Makes the Longines Nato feel like a bargain….

  2. Reviewers have to stop calling these watches “true” GMT. The other top is not “false”. One is either a travel GMT (in this case) or a caller GMT. Calling it a true GMT disparages the other kind.

  3. The use of the term “False” means what it is, i.e., It is not a “True” GMT. with it’s very convenient to use mechanism. The ‘False” really should not be called a GMT watch derivative at all. There is no real need for a “False” watch as the prices of a “True” GMT have dropped to make even Seiko cobbler them. Nuff said.

  4. 25,200vph and not 28,800vph? Better to have a smooth second hand sweep than long power reserve imho. So close, Longines!

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