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Seiko Updates Its Prospex 1965 Divers With The New SPB451, SPB453 & SPB455

A slightly reduced case size, improved water resistance and better power reserve make the Prospex 1965 range even better than it already was.

| By Robin Nooy | 5 min read |

Although Seiko’s expertise in waterproof watchmaking goes back a very long way, it wasn’t until 1965 that the Japanese manufacturer entered the professional dive watch market. Ever since, plenty of low- and high-end dive watches have been introduced with a good number of them becoming genuine icons. Collections like the 5 Sports, the Turtle, the Samurai, the Tuna and so on have all to an extent become evergreens. But throughout all of this history, one watch stands out as being a bit more special than others; the 62MAS. Partly because it was the very first dive watch by Seiko, but also because it was simply a damn-good watch. As Seiko brought the iconic design back to its portfolio of dive watches a couple of years ago, we get to enjoy plenty of modern reinterpretation of the 62MAS. New for 2024 is a trio of watches based on that very same design, yet with a couple of subtle but important updates. Here’s what you need to know.

The Origins

Plenty has been said before about the origins of the Prospex 1965 series, and it can all be traced back to one watch; Seiko’s very first diver, the 62MAS. Introduced in 1965 as reference 6217-8000 and nicknamed 62MAS, indicating the movement being part of the 62 calibre family and with MAS referring to “autoMAtic Selfdater” or “SeikoMAtic Selfdater”. The design of the original 62MAS is quite simple, with a sharp case, solid shoulders and a slightly curved profile, typical of the 1960s. It would become the benchmark for Seiko’s aquatic watches for decades to come and even today we can see traces of it in the brand’s modern dive watches.

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The 62MAS is a fan-favourite, and it makes perfect sense for Seiko to have brought it back as it did in 2017. The SPB053 was the first return to the 1965 design icon, and many editions have followed. This included models with different case sizes, new colours, artistic dial decorations and of course; new movements. But, through it all, the typical shape and profile of the 62MAS has been very much respected and only retouched here or there to make it even better. The overall flair is still very “retro” despite elements being enhanced or modernized in the process. In 2020 for instance, Seiko celebrated the 55th anniversary of the 62MAS with the very cool SLA037 re-creation and the SPB143, SPB147 and SPB149 trio. Now though, Seiko presents a new generation of Prospex 1965 Heritage Diver’s watches based on the 62MAS with the SPB453, SPB455 and special edition SPB455. But don’t worry, it’s again more evolution than revolution!

Finetuning the details

For 2024 Seiko has decided to slightly revise the overall design of the 62MAS reinterpretation whilst honouring the design codes of the original model from 1965. Seiko shaves a bit of the diameter, height and lug-to-lug dimensions, even though the differences are marginal. The diameter now comes in at 40mm across instead of 40.5mm, with the height dropping from 13.2mm to 13mm from top to bottom. The distance between the ends of the lugs is reduced to 46.4mm, making the SPB451, SPB453 and SPB455 by no means small watches, but at least a touch more wearable compared to the ones introduced in 2020 for instance.

And it’s not just the size that gets an update, as Seiko also improves the water resistance of the stainless steel case from 200m to 300m. Each of the three features a curved sapphire crystal, a unidirectional rotating diving bezel and an aluminium insert. The diving scale on the inserts is laser-engraved and filled with either white lacquer on the blue or black dials, or gold-coloured lacquer on the special edition charcoal model to celebrate Seiko’s 100th anniversary. The screw-down crown is recessed into the case ever so slightly, another update that separates these three from the previous generation.

The updates continue on the dial as well, which comes in the aforementioned blue, black or charcoal colours. Depending on which dial you prefer, you get either white, silver or gold-coloured raised indices and hands. To aid night-time legibility, everything is finished with LumiBrite inserts. Furthermore, the date has been repositioned to 04:30, and now has a circular window to reveal horizontally aligned digits, a nice aesthetic touch many brands seem to overlook. In the process, this means it also gets a full index at 3 o’clock, providing a bit more balance to the dial and compliance with the ISO norm. The finishing touches are the brand’s name, the Prospex logo and the reminder these are in fact automatic watches with a three-day power reserve and water resistant to 300m.

New Mechanics

The updates are not only aesthetical, as Seiko also improves the mechanical side of the Prospex 1965 series, with a new movement ticking away inside. The Calibre 6R55 these three new references rely on has an extended power reserve of 72 hours over the 70 hours the 6R35 calibre provided in the Prospex 1965 SPB213J1 and others. This marks the first time this calibre is used in the Prospex range but it will surely won’t be the last we see of it. And seeing it is metaphorically here, as the movement is covered by a solid steel caseback adorned with the Seiko wave emblem in the centre. The 6R55 runs at a rate of 21,600vph, and comes with central hours, minutes and seconds, as well as a date indication.

Seiko puts the new Prospex 1965 references on a slightly redesigned three-link steel bracelet, with shorter links and a smaller clasp, all in the pursuit of more comfort. All three models will be available at Seiko Boutiques and selected retail stores worldwide from June 2024 onwards, and will have a sticker price of EUR 1,400 for the blue SPB451 and black SPB453, and EUR 1,600 for the charcoal & gold-coloured SPB455 special edition. For this higher price, you also get a braided NATO-style textile strap made entirely of recycled plastic bottles (minus the steel hardware).

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12 responses

  1. I’d prefer a thinner watch with reduced water resistance. Most don’t dive, but everyone appreciates thinner watches.

  2. So the mid range divers will have better WR than Marinemaster. Things don’t seem to line up. Hopefully there will be new Marinemaster models out soon.

  3. Me every seiko release: Takes a huge mouthful of water, go straight to the prices. *Dramatic spray ensues*

  4. Awesome incremental update to an already great watch. The date placement is a lot less disruptive, and the colorways are elegant. And Seiko is doing it with the most modest of price increases (lower than inflation over the same period by my estimation) over the 2020 release.

    Thank you for the hands on and good photos. Keep up the good work.

  5. If pay up if they increased accuracy and got it a better bracelet. Accuracy will probably be fine as long as I buy it from an AD though (getting a regulation in the process), but they should really update the clasp and dive extension when charging this much

  6. I don’t think the 62mas user will like the round date window between the 4 and 5 that much to be honest.

  7. @hank – we don’t have the exact weight, but there shouldn’t be much difference with the SPB143, since the overall construction is almost identical.

  8. Looks like some good incremental updates. The new 6R5X family of movements have been very good in my experience so far (SPB381). Yeah the RRP is overpriced, but nobody pays retail for Seiko. You should be able to get this 25% cheaper in a couple months, and I think that’s a fair deal at that price level.

  9. Would love to see more shots of hear a description of how the blue dial looks irl. How prominent is the sunburst and is it a light or a deep blue?

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