Ti-MNPara Strap 24mm - Black

The Marine Nationale strap was not designed in a workshop. It was improvised at sea.

In the 1960s, the French Navy was issuing dive watches to its combat swimmers, the Nageurs de Combat of Commando Hubert, without straps. Tudor Submariners, Doxa Sub 300T, Jacques Bianchi JB300, Triton, ZRC. The watch heads arrived. The means of wearing them did not. Faced with the need for a strap that could be sized in the dark, adjusted over a 7mm neoprene wetsuit, and survive repeated salt water immersion, the operators reached for what they had on hand: surplus elastic webbing recovered from French-issue parachute rigging. They cut it, stitched it, fitted it with simple metal rings and a folding hook closure, and went to work. The result, recognizable today by its olive-and-yellow or red-striped weave, became one of the most quietly influential pieces of military horological gear of the 20th century.

That original field-made strap is the direct ancestor of every modern Marine Nationale style strap on the market. The reference Tudor 9401 dated 1977, now held in the Tudor archive, is documented as having been issued with a strap fashioned from parachute belting. Tudor itself acknowledged this heritage publicly in 2021 when it formalized its partnership with the Marine Nationale and launched the Pelagos FXD, a watch built around fixed lugs specifically designed for through-passing elastic strapping.

The SPD Ti-MNPara takes the original concept and rebuilds it for the modern wearer who carries a watch alongside other tools. We start with a heavy nylon webbing woven with Spandex, which holds its elastic memory significantly longer than the generic rubber-cored elastics used in lower-grade straps. We then replace every piece of metal hardware with Grade 5 6AL-4V titanium: both keeper rings, the buckle, and the closure. Titanium delivers three properties stainless steel cannot. It is fully non-magnetic, so it will not become magnetized by rare earth magnets used in modern wallets, key fobs, and EDC pouches, and it will not transfer that magnetism to the movement of a mechanical watch. It is fully corrosion-proof, indifferent to salt water, sweat, and chlorinated pools. And it is roughly 40% lighter than stainless at equivalent strength.

The non-magnetic property matters most to the wearer who pairs a watch with a wrist-mounted compass. Stainless hardware, once magnetized through prolonged contact with strong magnets, will deflect a compass needle by several degrees. Titanium will not. The Ti-MNPara is built to be worn with the PDW Expedition Watch Band Compass Kit, a wrist compass, or any field-grade navigation tool without introducing magnetic error into the bezel.

Carryology named the SPD Ti-MNPara a Best New Carry selection in February 2023. The 24mm strap width was designed to fit 44mm case Panerais. It works on whatever you put it on, as long as the lugs measure 24mm and with removable spring bars.

Find a way or make one.

Specifications:

• Titanium
• Nylon with Spandex

• Strap Width: 24mm
• OAL: 142mm (min) - 253mm (max)
• Strap Thickness: 2.00mm

• 0.4oz / 11.34g

• Most Adjustable and Comfortable Nylon Type Strap Available
• Fits Watches with 22mm Lugs
• Black Strapping
  
• Rings and Clasp 100% Non-Magnetic
• Rings and Clasp 100% Corrosion-Proof
• Best in Class Durable and Pliable Woven Nylon with Spandex
• 100% Titanium Hardware
• Secure and Easy On/Off Clasp
• Fits XS to XL Wrists
• Easily Adjusts Over Wetsuits
• Not recommended for quartz watches with sensor backs.

• Laser Etched SPD Kraken Trident

• Carryology Best New Carry, February 2023

FAQ

What is a Marine Nationale watch strap?

A Marine Nationale strap, sometimes shortened to MN strap, is an elastic single-pass watch strap originally improvised in the 1960s and 1970s by combat swimmers of the French Navy, the Marine Nationale, using webbing recovered from military parachute rigging. The original strap typically used a folding metal hook and two keeper rings. It allowed the diver to size the strap over a wetsuit, retain the watch against the wrist under load, and adjust in seconds without buckle holes or pins. The PDW Ti-MNPara is a modern interpretation of that original field-made design.

What is the difference between the PDW Ti-MNPara and a standard Marine Nationale strap?

Two material differences and one performance difference. First, the PDW Ti-MNPara uses 100% Grade 5 6AL-4V titanium for every piece of hardware, where most MN straps on the market use stainless steel or plated brass. Second, our webbing is a woven nylon and Spandex blend chosen for elastic memory retention, where many MN straps use rubber-cored elastic that fatigues over time. The performance result is a strap that is fully non-magnetic, fully corrosion-proof, and significantly lighter than a stainless equivalent.

Why does titanium hardware matter on a watch strap?

Three reasons. Titanium is non-magnetic, so the hardware cannot be magnetized by contact with rare earth magnets in modern wallets, phone cases, key fobs, and EDC pouches. A magnetized strap will magnetize a mechanical watch movement and will deflect any wrist-mounted compass, both of which are real failure modes for field users. Titanium is also fully corrosion-proof in salt water, sweat, and chlorinated water, where even 316L stainless will eventually develop crevice corrosion. And titanium is roughly 40% lighter than stainless at equivalent tensile strength.

Will the Ti-MNPara fit my watch?

The Ti-MNPara fits any watch with 24mm lug width and removable spring bars. This size was intended to fit 44mm case Panerais. If your watch has 24mm this strap will fit.

Can I wear the Ti-MNPara with the PDW Expedition Watch Band Compass Kit?

Yes, and this is one of the reasons it was designed the way it was. The PDW wrist compass features a split mounting slider allowing to fit over the elastic strapping in-between the buckles. Wrist-mounted compasses are highly sensitive to magnetic interference from nearby ferrous hardware. A stainless steel strap, once magnetized through extended contact with rare earth magnets, will introduce several degrees of deflection into a compass bezel reading. The titanium hardware of the Ti-MNPara is fully non-magnetic and will not influence the compass needle, making it the correct strap pairing for any navigation-capable watch setup.

Is the Ti-MNPara safe for use with my mechanical watch?

Yes. Because the hardware is titanium and fully non-magnetic, it cannot transfer magnetic charge to the watch movement. Magnetization is one of the most common causes of timekeeping error in mechanical watches and is increasingly common in modern daily carry because of the prevalence of rare earth magnets in wallets, sleeves, and bag closures. The Ti-MNPara isolates the watch from that risk. Note: not recommended for quartz watches with skin-contact sensors on the case back, as the elastic webbing can interfere with sensor contact.

How do I size the strap to my wrist?

The Ti-MNPara is a single-pass elastic strap. You thread the strap through the spring bars of the watch, around the wrist, through the keeper rings, and secure it through the clasp. The elastic webbing allows the strap to stretch slightly over the hand and then contract to wrist size, holding the watch firmly in place. Length is adjustable by feeding more or less webbing through the keeper rings before securing. Total adjustment range is 142mm to 253mm, which fits XS to XL wrists and accommodates wear over a wetsuit.

What is the history of the Marine Nationale strap?

In the late 1950s and through the 1960s and 1970s, the French Navy issued dive watches to its Nageurs de Combat, the combat swimmer unit known today as Commando Hubert, without straps. The watches arrived as bare watch heads. Operators sourced or fabricated their own straps in the field, frequently using elastic webbing salvaged from military parachute rigging. Tudor archive records reference 9401 dated 1977, fitted with a strap made from parachute belting, as a documented example. The improvised design proved so well-suited to underwater and field use that it has been replicated commercially ever since, and was formally acknowledged by Tudor in 2021 with the launch of the Pelagos FXD, designed specifically for through-passing elastic straps.

Is the Ti-MNPara made in the USA?

The Ti-MNPara is designed by Prometheus Design Werx in San Francisco. Hardware is formed from Grade 5 6AL-4V titanium and the webbing is sourced and assembled to PDW specification in Asia.