How to fit a NATO strap: step-by-step video guide
Remove a metal bracelet and fit a NATO strap in minutes. Full guide with workshop videos: Bergeon 6767F tool, Rolex GMT-Master and dive watch. Spring bars included with every order.
A NATO strap fits in a few minutes, with no particular skill required. Its pass-through design — a single piece of nylon running under the case — does however call for a precise method.
This guide covers the fitting step by step, first on a Rolex GMT-Master then on a dive watch, illustrated by our own workshop videos.
Our full selection: NATO straps, available in 18, 20, 22 and 24 mm.
Before you start: removing the strap in place
If your watch still carries its steel or leather strap, it must come off first. This step needs a fine-forked tool — the Bergeon 6767F tool is the professional reference, and the one we use in the workshop.
Keep the spring bars: they will hold the NATO. If they are bent or oxidised, replace them with stainless steel bars of the same size.
The full method, for drilled and solid lugs alike, is covered on video in our guide: removing a watch strap.
Fitting a NATO strap to a Rolex GMT-Master
A NATO fits differently from a conventional strap. Here is how to proceed.
Video demonstration: removing the steel bracelet and fitting a NATO on a Rolex GMT
Step by step
- Slide the first spring bar into the lug at the 12 o'clock side
- Pass the end of the NATO, the buckle end, under the bar, between the case and the strap
- Seat the bar in the second lug
- Run the long section of the NATO under the case, towards 6 o'clock
- Lock the NATO with the short remaining section, as shown in the video
- Check that the strap is centred under the case and that both bars are properly seated
- Once on the wrist with the buckle closed, the excess length folds into the last keeper
The watch then rests on two passes of nylon. This is what gives the NATO its pass-through security: even if one spring bar were to fail, the watch would remain held on the wrist by the second pass.
Fitting a NATO strap to a dive watch
On a dive watch — Omega Seamaster, Seiko Prospex, Tudor Black Bay — the method is the same, but a few points deserve attention.
Video demonstration: fitting a NATO to a dive watch
Points specific to dive watches
- 20 or 22 mm depending on the model — always check the lug width before ordering
- The thicker case, screw-down back or double back, makes the nylon a little tighter to pass at first. That is normal; the nylon softens with use.
- Curved lugs, on the Omega Seamaster in particular, call for slightly more care when engaging the bars — take the time to centre properly
- On watches rated to 200 m and beyond, a NATO can be worn diving. That is one of its historic advantages.
Which NATO strap width should you choose?
The strap width must match the lug width of your watch exactly — the distance between the two lugs of the case, in millimetres. An error in width makes fitting impossible.
- NATO 18 mm — vintage watches, dress watches, classic chronographs
- NATO 20 mm — Rolex Submariner, GMT-Master, Omega Seamaster and Speedmaster, Hamilton Khaki Field, Seiko SKX
- NATO 22 mm — modern large-diameter dive watches, Jaeger-LeCoultre Master Compressor
- NATO 24 mm — Panerai, large military watches
If in doubt, our watch strap size guide gives the lug width for 245 models.
FAQ — Fitting a NATO strap
Do I need a special tool to fit a NATO strap?
To remove the original strap, yes: a fine fork is strongly recommended to avoid scratching the case. To fit the NATO itself, no tool is needed — it goes on by hand.
Can a NATO be fitted without removing the spring bars?
No. The bars hold the NATO in the lugs. They must be taken out of the previous strap and reused. If they are bent or rusted, replace them with stainless steel bars of the same size: a 20 mm watch takes 20 mm bars.
Does a NATO strap come off easily?
Yes, and that is one of its great advantages: a NATO slides off without any tool, with the spring bars left in place. Many collectors rotate between several NATO straps according to the outfit or the season.
My NATO strap is too long, what should I do?
A NATO is around 27 cm in total length and suits wrists from 16 to 24 cm. The excess folds into the last stainless keeper. No cutting is necessary or advisable.
Can a NATO be fitted to any watch?
To any watch with standard spring bars, which covers the great majority of the market. Watches with an integrated bracelet — Royal Oak, Nautilus, Overseas — are not compatible with a standard NATO.
Is a NATO strap suitable for diving?
Yes, and that is the use it was originally designed for. Woven nylon resists seawater, dries quickly and does not deteriorate with repeated immersion.
Our NATO strap selection
All NATO straps NATO 18mm NATO 20mm NATO 22mm NATO 24mm Marine Nationale
NATO James Bond black grey 20 mm · NATO black nylon 20 mm
Going further:
Removing a watch strap — video guide
The history of the NATO strap
How to choose a watch strap — size guide
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