The History of NATO Straps

Nylon military watch straps have a deep-rooted history. The first reference to what we now know as a NATO strap appeared in the 1968 British Ministry of Defence (MoD) specification 66-4 as "Strap, Wrist Watch - Nylon." Straps of somewhat similar design using leather, canvas, and cotton webbing materials dating from the early to mid-1900s exist, but those straps are outside the scope of this article.

Glossary:

• MoD British Ministry of Defence
• DefStan Defence Standard
• NSN Nato Stock Number

Circa 1954 or 1958 (details are sparse), the first nylon watch strap, 6B/2617, was issued by the RAF with the 6B/346 watch (Mark XI, supplied by JLC and IWC). The strap's nylon webbing had a "ribbed" appearance in comparison to the later "straight cross weave" nylon of the DefStan 66-4 straps.

The 6B/2617 straps were 16mm wide and 270mm long, with a two-layered design like the DefStan 66-4 straps. However, they were not yet assigned a NATO Stock Number (NSN), which is where the colloquial "NATO" name comes from.

^{An original 6B/2617 strap. Credit: geo7863 / MWR}

DefStan 66-4 included the first definition of what is now called a "NATO" strap. Although it primarily concerned "Watches, Wrist, Divers'," DefStan 66-4 featured details about a new type of nylon strap available with the watch or on its own.

Section 11 of the specification (seen below) codifies the strap as Nato Stock Number 6645-99-124-2986, and as the story goes, they later became known simply as "Nato straps."

DefStan 66-15/2 added Nato Stock Number 6645-99-527-7059 for RAF-issued straps, which were leather & nylon. Oddly, there is no specification for that strap type within any of these Defence Standards.

Specifications from DefStan 66-4 include: 

• 18.5mm width
• 1.2mm thickness
• 280mm length
• Chromium-plated brass hardware
• Buckle recess for the prong
• Woven nylon with welded joints
• Straight cross weave
• Steel grey color
• End of strap to be sealed

DefStan 66-15 moved the strap to its own specification rather than being part of the prior watch specification. The new specification included much more detailed information on the construction and materials.

Notably changed since DefStan 66-4:

• Width changed to 18.0mm +/- 0.5mm
• Brass hardware testing method changed to British Standard (BS) 2782
• Color specification Admiralty Grey BS 4800, Card, 3, Ref 18B25 (from the more vague steel grey)

The most recent revision to the MoD strap design is 2001's DefStan 66-47/2 "Strap, Wrist Watch." Although DefStan 66-47 dates back to January 1992, the 2001 revision (Issue 2) changed the strap width from 18mm to 20mm +/-0.5mm. The material, hardware, and length specifications remained the same.

This DefStan specification has since been cancelled, possibly in 2011 or 2012. It is not clear if there is a current, active Defence Standard for the Strap, Wrist Watch (Nylon).

18mm width straps were reportedly still available after the DefStan 66-47 update, which superseded the 20mm width for NSN 6645-99-124-2986. We have not come across a distinct stock number for the 18mm strap versus the 20mm strap post-DefStan 66-47.

It is said that black and olive green colored straps were also offered in addition to Admiralty Grey, but we could not find a distinct stock number for those variations.

Some straps were made at 270mm in length in the 1970s, even though the standard has always been 280mm.

At some point (possibly in the 1990s), stainless steel hardware started appearing on MoD straps, but the Defence Standards have always specified chromium-plated brass hardware.

^{An incredible MoD strap collection of great variety. Credit: cwcaddict.com / "An Addiction to Old NATO Straps"}

Phoenix Straps Limited and Cabot Watch Company (CWC) have supplied the Ministry of Defence with NATO straps. Still, we cannot locate any contractual proof or corroborated timeframes. Apparently, "M. Furst & Co." supplied 6B/2617 straps in the 1950s, but it is not clear if they later produced NSN 6645-99-124-2986 straps. 

We found anecdotal evidence that Phoenix started supplying the MoD with straps in 1978 and CWC in 2018. CWC has a blog post stating that they were supplying straps in 2016. It is unclear if any supplier was ever exclusive or if multiple manufacturers were supplying straps concurrently.

A post on MWR suggested that CWC was supplying the MoD with strap-less watches, and the MoD then fitted them with Phoenix straps. We could not find any proof of this.

CWC's history states they still supply watches and straps to the British Forces today. In late 2023, Phoenix Straps Limited announced its forthcoming closure due to the owner's retirement. Phoenix continues to sell old inventory on eBay but don't seem to be manufacturing new straps anymore.

Thank you to cwcaddict.com for their great MoD strap article and for sharing the DefStan PDF documents. Thanks to the Military Watch Resource forum members for their incredible research and deep knowledge base. Thank you, geo7863 for sharing the great photo of the original 6B/2617 strap.

Our Defense NATO strap remains faithful to the classic MoD design while incorporating thoughtful improvements. Since we are not bound by MoD supplier constraints, we refined key details for a better fit and feel. Learn more by checking out the straps below.

Crown & Buckle offers a wide variety of NATO and similar nylon watch straps, from modern Supreme NATOs to innovative Chevron Adjustable straps and many in between, with a broad range of price-points. We've included a small sampling below to spur your inspiration.