Nothing to see here people, please move along. No, wait! Those straps are new! Indeed, the strapping Prospex 1965 and 1970 Diver’s Modern Re-interpretation watches are outfitted with brand new artisanal straps. Four colors in total are made by using seichu, a traditional Japanese braiding technique that results in very strong and striking fabric straps.

The Prospex 1965 Diver’s Modern Re-interpretation SPB239 looks familiar, doesn’t it? That’s because Seiko introduced quite a few versions on the 1965 theme already. There’s the SPB149J1 with its special 55th anniversary blue-gray dial and steel bracelet for instance, or the SPB147J1 with a chocolate brown dial, gold-colored hands, and silicone strap.

It’s the strap that sets this new re-interpretation apart.

These re-interpretations of Seiko’s famous 62MAS diver’s watch are characterized by a slim profile and a lowered center of gravity that makes it comfortable to wear. The new SPB239 has a deep dark brown dial and a unidirectional bezel with cream-colored accents. It’s the strap that sets this new re-interpretation apart.

Strapping Prospex 1965 And 1970 Diver’s Modern Re-interpretation Watches

More structure

The straps that Seiko is debuting for its strapping Prospex 1965 and 1970 Diver’s Modern Re-interpretation watches are carefully manufactured with a special technique used in Japan called seichu. At first glance, they look like NATO straps — largely because the way the straps are attached to the watch is indeed the same as a NATO strap — but when you look a little closer the differences start to appear. Because of the braiding technique the straps are more structured.

… despite being supple and soft, the seichu braided straps sit firmly on the wrist.

A regular nylon NATO strap has a very fine, woven structure. And the strap is often quite thin. These polyester straps from Seiko, are thicker and have a more pronounced texture. Because of that added thickness and clearly visible braiding pattern, the straps don’t only look more luxurious, but they also feel that way. They’re supple and permit air to flow through, thus avoiding a sweaty wrist in warm conditions.

And despite being supple and soft too, the seichu braided straps sit firmly on the wrist. Coming back to nylon and polyester, it’s maybe interesting to note that nylon is more durable and weather-resistant than polyester. Both fabrics are flame retardant, but nylon is stronger, while polyester is more heat-resistant. Nylon is also a bit softer than polyester. Still, Seiko uses polyester for these braided straps and the result is quite something.

The difference between weaving and braiding

Now that you know the difference between nylon and polyester, it’s time to address the difference between weaving and braiding. I found Sharon Kersten, a weaver for over fifteen years, to explain the difference between the two techniques. She says that “a weave as in ‘weave fabric’ has separate warp (long-wise elements) and weft (back and forth or shorter-wise) elements. In a braid, the elements take turns being both the warp and the weft.”

… the seichu straps have four times the tensile strength of a regular fabric strap …

That’s pretty interesting stuff. Even from that short description, I think it is easy to get at least a sense of how strong braiding can be when done properly. Unsurprisingly, therefore, the seichu straps have four times the tensile strength of the regular fabric straps Seiko uses. That is a feature that serious divers will surely appreciate.

Strapping Prospex 1965 And 1970 Diver’s Modern Re-interpretation Watches

A high performance caliber

The specifications of both Prospex 1965 and 1970 Diver’s Modern Re-interpretation watches are pretty much the same. Both watches are water-resistant to 200 meters and the caliber Seiko chose for these two models is the automatic 3hz caliber 6R35. Seiko refers to this movement with 70 hours power reserve as a high performance caliber. If you want to wind the movement manually, you have to turn the crown a minimum of 55 times to get a full charge from a totally flat starting position.

The claimed accuracy of the caliber 6R35 is rated at -15/+25 seconds per day in normal temperature conditions. Whether or not those performance specs match up with the prices, however (€1,250 for the SPB239 and €1,350 for the SPB237), is open for debate.

The faded look of the bezels in earth tones also play the retro card …

Both the traditional-looking SPB239 and the more exotic Captain Willard SPB237 have hands and indexes coated with Lumibrite in a vintage-looking color — that’s a less loaded way to describe faux patina. The faded look of the bezels in earthy tones also play the retro card (expertly, I might add) and the same goes for the curved sapphire crystal with anti-reflective coating.

Strapping Prospex 1965 And 1970 Diver’s Modern Re-interpretation Watches

Strapping Prospex 1965 And 1970 Diver’s Modern Re-interpretation watches: the differences

The biggest difference between the SPB239 and the SPB237 are the case shapes, of course. The case of the SPB239 measures 40.5×13.2mm. While the Captain Willard may have the same height, it has a larger diameter of 42.7mm. And like the SPB239, the SPB237 it has a familiar look — you might recognize the strong features of the black SPB151 and  green SPB153 Captain Willard.

The artisanal seichu straps definitely play a big role in boosting the appearance of both new Prospex models.

Both watches come with an additional seichu strap. The SPB239 comes on a dark brown braided strap and an extra sand-colored one. The SPB237 comes on an army green strap, but you can change that to a gray one for a fresher look.

Strapping Prospex 1965 And 1970 Diver’s Modern Re-interpretation Watches

The artisanal seichu straps definitely play a big role in boosting the appearance of both new Prospex models. The more prominent structure reminds me of a judo or karate belt, but it is also used in the oft-decorated cords that hold a kimono in place. I obviously get confused and seem to mix up senseis and geishas here… And I never for once thought that it was a shame Seiko opted for seichu straps in polyester instead of nylon.

I find the fashionable colors very attractive too. But perhaps best of all is the solid hardware. These straps make an already strong argument for these two new Prospex models even stronger. Hopefully Seiko will make these straps available separately too. I would love to see them on some of the other models in the range, and in even more colors too! For more information please visit the Seiko website.

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