Every Pelagos FXD before this one was built for people who go underwater. The GMT was built for people who go up.
That sounds like marketing, but it changed the watch in a way that matters directly to you: Tudor redesigned how the strap attaches to your wrist. And on a watch that physically cannot wear a bracelet, that is not a detail.
Strap size and fit guide (read all of this — the FXD family is not uniform)
Your Tudor Pelagos FXD GMT (Ref. M2542G247NU) is 42mm with a 22mm strap width, and — critically — it has fixed strap bars machined into the titanium case. They do not come out. Ever.
That means only a single-piece, pass-through strap will fit. A conventional two-piece strap cannot be installed on this watch at any width, because there is no way to get it around the bar.
Order from the Pelagos FXD range on Helvetus. Those straps are built for this exact mounting system, so there is no fit option to choose — only a colour.
Now the family map, because "FXD" now covers four different watches and they do not all share a case:
| Watch | Case | Strap |
|---|---|---|
| Pelagos FXD GMT "Zulu Time" | 42mm titanium | 22mm, fixed bars |
| Pelagos FXD (blue MN / black USN / Alinghi) | 42mm titanium | 22mm, fixed bars |
| Pelagos FXD Chrono | 43mm carbon | 22mm, fixed bars — different case |
| Pelagos 42 (25500 / 25600) | 42mm titanium | 22mm, standard spring bars |
The GMT shares its case with the original 42mm titanium FXDs, so anything cut for those is correct for this watch. The two to watch are the Chrono, which is a different 43mm carbon case, and the Pelagos 42, which looks similar and is also 22mm but uses ordinary spring bars — so its straps will not thread onto your fixed bars.
Checklist: 42mm, 22mm, fixed bars, single-pass only, order from the Pelagos FXD range.
What changed with the GMT — and why it affects your strap
Tudor built this one for the Aéronautique Navale, the French Naval Aviation, rather than for the combat divers the FXD was originally designed around. The case is the same satin-brushed grade 2 titanium, 12.7mm thick with a 52mm lug-to-lug, still rated to 200m, still with a grade 5 titanium caseback engraved with the naval aviation anchor and the year of production.
What is different is everything to do with wearing it.
The closure changed. Previous FXD models used a hook-and-loop fastening — infinitely adjustable, ideal over a wetsuit, and designed for someone getting in and out of the water. The GMT ships instead on a single-piece woven strap with a titanium pin buckle. Reviewers who have lived with it make the same point: you gain a cleaner, more presentable watch and you lose the infinite adjustment. On a pin buckle you are choosing between fixed holes, so getting the length right matters more on this reference than on any other FXD.
And Tudor's own military spec assumes you own more than one. The aviators actually issued this watch receive two straps — one for the summer uniform and one for the winter uniform. The version sold to the public comes with one. That is not a marketing line; it is how the watch was specified for the people it was designed for, and it is the most honest argument for a second strap anywhere in the Tudor range.
There is one more thing worth knowing before you choose a colour. The 24-hour Zulu hand is finished in bright orange lacquer, and that is not decoration — it is colour-coding, so an aviator can find universal time instantly on a black dial in a dark cockpit. Everything else on the watch is deliberately neutral: matte black dial, black ceramic bezel insert, brushed titanium, and a warm beige-toned luminous material. One colour, doing a job. The best straps here leave it alone.
The best straps for the Pelagos FXD GMT
Navy Blue / Grey — the hero. This is the one that suits what the watch actually is. The grey sits tonally with brushed grade 2 titanium rather than contrasting against it, and the two-tone weave breaks up a 52mm lug-to-lug so the watch stops reading as one long dark bar on the wrist. Most importantly, it adds no colour of its own, which leaves the orange Zulu hand as the only coloured thing on the watch — exactly as designed. If you want the GMT to look like the instrument it is rather than a fashion object, start here. Navy Blue/Grey Tudor FXD Strap
Green / Red — and it is more historically correct than the factory strap. Here is a genuinely good bit of trivia with a practical payoff. When Tudor describes the straps the French Navy actually used on its watches historically, it names two: black braided nylon, and — less commonly — handmade straps made from parachute elastic, recognisable by their green colour with a yellow or red central thread.
Read that again, then look at this strap. Green, red central thread. Tudor's own factory strap for the GMT is a plain green chosen to match modern flight-suit fabric; this one matches the older military straps the whole FXD concept was built to honour. It is warm against the beige lume, it looks properly period on a brushed titanium case, and it is the strap that will get asked about. Green/Red Tudor FXD Strap
Navy Blue — the one you will wear most. The quiet option, and the one to buy as the second strap if you take the two-strap logic seriously. Solid navy goes almost black in low light against the matte dial and ceramic bezel, then reads clearly blue in daylight, so it does the same trick the watch's own lume does — different in different conditions. It is also the most anonymous of the three, which is the right quality in a watch you want to wear without thinking about it. Navy Blue Tudor FXD Strap
See the full range built for this mounting system here: All Tudor Pelagos FXD Straps
Getting the order right
Three things and you cannot go wrong: it is 42mm, it takes 22mm, and it has fixed bars so the strap must pass through in one piece. Order from the Pelagos FXD range and the mounting is handled for you.
If you own other Tudors:
- Best Straps for Tudor Pelagos FXD 25707B — the original 42mm titanium FXD, same case, same straps
- Tudor Black Bay GMT "Pepsi" 79830RB Strap Guide — Tudor's other GMT, 41mm and 22mm, but standard spring bars and a completely different colour brief
FAQ
What strap size is the Tudor Pelagos FXD GMT? 22mm, on a 42mm titanium case. But the width is only half the answer — the bars are fixed, so the strap has to be a single-piece pass-through design.
Can I fit a normal two-piece 22mm strap? No. The bars are machined into the case and cannot be removed, so a two-piece strap has no way to attach. Single-pass only.
Will a Pelagos 42 strap fit the FXD GMT? No. The Pelagos 42 is also 42mm and also 22mm, but it uses ordinary spring bars. Straps made for it will not work on fixed bars.
Does the FXD GMT use the same straps as the original Pelagos FXD? Yes. Same 42mm titanium case and same fixed-bar system. The FXD Chrono is the exception — that is a 43mm carbon case.
Why does Tudor supply two straps to issued personnel? One for the summer uniform and one for the winter uniform. Civilian buyers get one, which is worth knowing if you are deciding between one strap and two.
Is the FXD GMT rated to 500m like the Pelagos? No — 200m. The 500m rating with the helium escape valve belongs to the Pelagos 42.
Final thoughts
The FXD GMT is the rare watch where a strap is not an accessory or an upgrade. There is no bracelet, there never will be, and the strap is the only part of the watch you will ever change. That makes the colour decision a bigger one than usual, and it makes a second strap far easier to justify than on almost anything else you own.
Helvetus straps for the Pelagos FXD are built around the fixed-bar system, so they thread through cleanly and sit flat against the case. Shipping is free worldwide with no import costs, nylon straps are covered by a one-year warranty (our rubber straps carry a lifetime warranty), and more than 50,000 customers have already made the swap.
