The Tudor Black Bay 54 CNC: Commando Hubert, the 100th Combat Swimmer Course and the Perfect Strap

There are plenty of limited-edition watches that are created simply because a brand wants another limited edition.

Then there are watches with a genuine story behind them.

The Tudor Black Bay 54 CNC falls firmly into the latter category.

Created to commemorate the 100th Cours des Nageurs de Combat (CNC) — France's elite Combat Swimmer Course — this incredibly rare Black Bay 54 is directly connected to Commando Hubert, the French Navy's elite maritime special operations unit.

Only 100 examples were produced, making this one of the most unusual modern Black Bay 54s and, arguably, one of the most interesting military-connected Tudors of recent years.

What exactly is the CNC?

The Cours des Nageurs de Combat, or Combat Swimmer Course, is a gruelling 27-week programme conducted by the French Navy's diving school.

The course prepares candidates for the demanding world of combat swimming and maritime special operations, covering disciplines including oxygen diving, underwater navigation, demolition, combat swimmer operations and parachuting.

It is not exactly your average professional development course.

Only around 5–10% of those who begin the CNC successfully earn the combat swimmer qualification. For those who do, completion of the course provides the pathway to assignment with Commando Hubert.

The 100th running of the course was therefore a significant milestone, and Tudor produced a very special Black Bay 54 to commemorate it.

A very different Black Bay 54

At first glance, the CNC Black Bay 54 looks familiar.

The case remains the beautifully compact 37mm format that makes the BB54 so appealing, and the watch retains the vintage-inspired proportions that hark back to Tudor's first Submariner, the reference 7922 from 1954.

But look closer and the differences become obvious.

The dial has been stripped back considerably compared with the standard production model.

Gone are the usual certification and depth-rating markings, replaced by a much more utilitarian appearance. At six o'clock you'll find the individual “CNC xxx-100” numbering, while the “200m” text is printed in red.

It is a wonderfully simple detail, but it completely changes the character of the watch.

Rather than looking like a conventional luxury dive watch with a military-inspired colour scheme, the CNC feels much more like a purpose-built tool.

And that's exactly what makes it interesting.

The Tudor and Marine Nationale connection

The CNC Black Bay 54 also fits into a much larger story.

Tudor's relationship with the French Marine Nationale stretches back to the 1950s, when Tudor Submariners were supplied to French naval divers.

Those watches developed an incredible reputation for being tough, practical and suited to the realities of military diving.

The connection continued through generations of Tudor Submariners before eventually helping lay the groundwork for the modern Pelagos FXD.

Commando Hubert has played a particularly interesting role in this history.

Photographs from the 1970s show Commando Hubert operators wearing Tudor Submariners, providing a direct link between the watches being used by French combat swimmers decades ago and the modern CNC Black Bay 54.

 

Heres a strap that works incredibly well...

And this is where my Integra FKM strap for the Black Bay 54 comes in.

Some of the photographs accompanying this article show the CNC Black Bay 54 fitted to the Integra, and I think it makes a surprisingly good combination.

The Black Bay 54 is a relatively small and historically proportioned watch. At 37mm, it doesn't need an oversized or overly complicated strap.

The Integra keeps that same understated character while giving the watch a much more modern, functional feel.

Why FKM works so well on the BB54

The Integra is made from FKM rubber, a material particularly well suited to a watch like the Black Bay 54.

FKM is a high-performance fluoroelastomer known for its excellent resistance to heat, oils, chemicals and environmental exposure. More importantly for a dive watch, it provides a durable and flexible material that can cope with water, sweat and the general abuse that comes with actually wearing a watch outdoors.

And that's something I think suits the BB54 perfectly.

The original 1950s Tudor Submariner was a tool watch.

The CNC Black Bay 54 is connected to a modern military diving community.

So while a vintage parachute strap gives the watch an incredible historical connection, an FKM rubber strap gives it a different kind of practicality.

It's the strap I'd be reaching for if I wanted to actually take the watch out and use it.

The Integra also gives the CNC a slightly more contemporary appearance without completely losing the vintage character of the BB54. The combination of the compact 37mm case, black bezel and rubber strap keeps everything clean and understated.

It doesn't overpower the watch.

And that's important.

 

One watch, two very different personalities

This is probably my favourite thing about the CNC Black Bay 54.

Put it on the Heritage Commando Strap and you have a watch that tells a very specific story — Commando Hubert, Marine Nationale, parachute webbing and the 100th Combat Swimmer Course.

Put it on an FKM Integra and suddenly it becomes something else.

Still a military-inspired Tudor, but now a modern, highly practical everyday dive watch.

Neither option is necessarily better.

They're simply different.

And that's exactly what makes changing straps so enjoyable.

A watch can completely change personality without changing a single component of the watch itself.

A special Tudor with a genuinely interesting story

The CNC Black Bay 54 is one of those watches that becomes more interesting the more you learn about it.

The red “200m”.

The CNC numbering.

The 100-watch production run.

The 100th Combat Swimmer Course.

The connection to Commando Hubert.

The history of Tudor and the Marine Nationale.

And, of course, the Heritage Commando Strap made from original parachute webbing.

All of those details come together to create something that feels considerably more meaningful than a standard limited-edition release.

Whether the 100 CNC Black Bay 54s are ultimately used operationally or remain primarily commemorative pieces, they represent another chapter in one of Tudor's longest and most fascinating military relationships.

And for me, that's what makes watches like this so interesting.

It's not just about what's on your wrist.

It's about where the watch came from, who it was made for, and why it exists in the first place.

And if you want to change things up from the historically correct Commando setup, the Yorkshire Watch Straps Integra FKM for the Black Bay 54 makes a pretty compelling alternative — giving this very military Tudor a durable, modern strap that's ready for whatever you throw at it.

 

Built for adventure. Made to last.

Some of the photographs featured in this article show the Tudor Black Bay 54 CNC fitted with the Yorkshire Watch Straps Integra FKM strap for the Black Bay 54