Looking for a watch to travel and dive with in style? Maybe the new Longines HydroConquest GMT is something for you. There are four color versions to choose from — blue, black, brown, and green — and each has a unique character. The HydroConquest line launched back in 2007, and this redesigned GMT dive watch is the first one in the collection with dual-time functionality. The best benefit is probably that the new watch is a “flyer” GMT, making it a proper travel watch.

Some people argue that a dive watch doesn’t need a complication. Even a date is often considered too much. I partially agree but only if you find yourself in a spot in this world where diving is pleasant all year round. Most people, however, find themselves in places that either don’t offer dive spots or ones that are only enjoyable during a (short) summer. Finding waters to enjoy a good dive often means traveling both through and to different time zones. And there you have it: a dive watch with a GMT function makes pure practical sense. Now that we have that out of the way, let’s focus on the watch itself. In this particular case, it’s the green, gilt-tone, and cream version of the Longines HydroConquest GMT with reference number L3.790.4.06.6.

Longines HydroConquest GMT

Longines HydroConquest GMT: a redesigned shiny diver with benefits

Before you plunge in, you can check what time it is at home. The knowledge that the ones left behind are getting ready for work will only make you enjoy the underwater world even more. The HydroConquest GMT is a bringer of joy in that sense, and it brings it in a robust 41 × 12.9mm steel case. On the steel H-link bracelet with a double-safety folding clasp and micro-adjustments, the watch weighs a hefty 180 grams. “Too heavy,” you say? Well, you’re going to wear it on your wrist, not stuff it in your luggage, so it all comes down to how those 180 grams feel on the wrist.


Let’s start with the looks first, though. And that’s because there’s just no getting around them. The green, gold, and cream HydroConquest GMT is quite shiny. Yes, there are some satin-finished surfaces too, but the polished parts take center stage. The green sunray dial is also quite prominent, and the gilt-tone polished hands and hour markers coated with creamy Super-LumiNova provide a neo-retro look that people still go crazy about.

HydroConquest GMT

Not retro at all on the inside

The HydroConquest GMT might have a retro-inspired dial design, but the shape and size of the case definitely aren’t. This case sits well on the wrist, but it’s also quite stocky. Yes, up to a point, it has to be because how else do you achieve water resistance to 300 meters? Still, there’s a bit of a discrepancy between the vibes of the dial and the case shape; the classic and contemporary design elements don’t really blend softly and fluidly. Instead, they transition sharply.

More modernity is found inside the case and under its screw-in stainless steel case back. There lies the self-winding ETA-based Longines caliber L844.5. Like most Longines mechanical watches, it beats at 25,200 vibrations per hour. The movement uses a silicon balance spring and other components in non-magnetic materials. This results in a caliber that’s ten times more resistant to magnetic fields than the ISO 764 benchmark standard. And the L844.5 movement also has a power reserve of up to 72 hours.

Longines HydroConquest GMT

Some practical throwbacks

Yes, the HydroConquest GMT is a super functional and superior flyer/travel GMT that outclasses a cheaper and less practical caller/office GMT. So the hour hand for the local time can be moved forward and backward while the movement continues to run, and the date is connected to it. But there are two things to lament about. First, the 24-hour indications on the outside of the rehaut are very small and barely visible when you look at the watch frontally. And the color difference that distinguishes between night and day is also not the clearest, to put it mildly. Yes, the shades are subtle and all that, but from a functional standpoint, the combination doesn’t work well. Having said that, although I haven’t seen the other three versions of the watch in the metal, the black-dialed variant seems to be the most functional one with the best contrast.

An undoubtedly very functional element, though, is the unidirectional bezel with a ceramic insert showing a capsule in the triangle at 12 o’clock filled with beige Super-LumiNova. And to come back to the 180 grams, if you size the bracelet correctly, you won’t find the HydroConquest GMT with its rather average 49mm lug-to-lug length to be an unbalanced “arm anchor.”

HydroConquest GMT

Final thoughts on the HydroConquest GMT

My dear colleague Gerard will go nuts when he sees the new Longines HydroConquest GMT. Why? Because he just doesn’t get dive watches with a shiny sunray dial — you can bet your bottom dollar that he will write an article on the topic soon. But because this HydroConquest is both a diver and a GMT, less strict rules apply. This watch needs to work underwater but also look good while traveling from A(msterdam) to B(ali). However, as I wrote before, an easy-to-read, more contrasting 24-hour scale would also be quite useful. Also, Longines already has a very classy, somewhat-dressy GMT in the collection in the shape of the Spirit Zulu Time. To my taste, the new HydroConquest GMT in green, gold, and cream is a bit too much like that model instead of a more tool-like dive watch.

Anyway, let’s end with some final information regarding versions and prices. On the bracelet, all four versions of the HydroConquest GMT have a price of €3,150. If you want the watch on either a beige or a khaki-green NATO-style strap, the price is €3,050. And on either a blue or a black rubber strap with a micro-adjustable folding clasp, the travel diver will set you back €3,150.

More information on the first HydroConquest with GMT function can be found on the official Longines website.


Watch specifications

HydroConquest GMT
Green sunray with applied luminescent indices and 24-hour scale on the rehaut
Case Material
Stainless steel, ceramic bezel insert, screw-down crown
Case Dimensions
41mm (diameter) × 49mm (lug-to-lug) × 12.9mm (thickness)
Sapphire crystal with multi-layer antireflective coating on both sides
Case Back
Solid stainless steel, screw-in
Longines L844.5 — automatic winding, 25,200vph frequency, 72-hour power reserve, silicon balance spring
Water Resistance
Stainless steel H-link bracelet with double-safety folding clasp and micro-adjustment
Hours, minutes, seconds, and date at 3 o’clock, GMT function with a 24-hour hand, unidirectional 60-minute dive bezel
5 years