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The 62MAS-Inspired Seiko Prospex 1965 Diver’s Modern Re-interpretation SLA065

The high-end 62MAS-based watch is back, with some minor updates and a cool new textured dial.

| By Brice Goulard | 8 min read |
Seiko Prospex Diver Save the Ocean SLA065 Astrolabe Dial 62MAS-inspired

A couple of weeks ago, Seiko released a new dive watch as part of the SLAxxx series – the higher-end collection with the most advanced features the brand can pack. Once again, it had to do with the most emblematic dive watch of the brand, the 62MAS – which is also the brand’s first-ever and, coincidentally, Japan’s first-ever dive watch. As part of the “Save the Ocean” series, it felt familiar and shared many design elements with other eyes in the brand’s portfolio. However, this new Seiko Prospex Diver Save the Ocean SLA065 also came with some specificities – its dial, of course, and its colour scheme too, but also an unprecedented case. And now that we have had a sample in our hands, it’s time to tell you everything you need to know about it.

Our initial article was deliberately short and factual. First of all, Seiko is often rather concise when it comes to explaining its watches in press releases. Having only the brand’s official images in our hands isn’t enough to make an impartial judgement. Second, we knew the test watch was coming soon after the release, which is why it is now time to move away from facts alone and introduce more feelings into the equation. There’s also the need to answer some questions regarding materials and price… This new SLA065 is an expensive model considering Seiko’s standards. But for a reason.

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The Seiko Prospex Diver Save the Ocean SLA065 is yet another interpretation of the brand’s most iconic and important dive watch ever, the 62MAS. We’ve seen many re-editions and re-interpretations in the past, but this new model comes with its own specifications. What is a 62MAS? Seiko today is often regarded as one of the most legitimate brands in the field of diving, and it is all because of this 1965 watch, the reference 6217-8000, which is mainly known in the collecting community as the 62MAS – MAS being an acronym for “autoMAtic Selfdater”. It was the first dive watch of the brand and the first of its kind produced in Japan. Important, to say the least.

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This watch had an enormous influence on future models, and several current Seiko Prospex Diver watches still rely on some of its design elements. It took some time for the brand to enter the race (Rolex and Blancpain started in 1953, Omega in 1957…). The 62MAS is as classic as it can be, with its 37mm steel case, sharp design, and solid shoulders. It’s still relatively simple, without crown guards and a crown positioned at 3 o’clock. The dial is also reasonably simple, yet efficient – large hands and markers, generous lume – framed by a thin 60-minute bezel. Its 150m water-resistance was nothing exceptional back in 1965, and the movement was solid, but then again, quite classic. What matters now is the overall design, which has been a great source of inspiration for the brand.

The 62MAS shape has been used multiple times in the past. We’ve seen a highly faithful re-edition in 2017 with the SLA017, followed by a slightly modernised version with the SLA037. There are also several more accessible models to mention, all considered Modern Re-interpretation watches. It started in 2017 with the SPB051 and SPB053, fairly large watches that failed to fully convince. Seiko rectified the situation in 2020 with the SPB143, SPB147 and SPB149 watches – more vintage-ish, more compact, more appealing and more convincing altogether. With this in mind, there are already many options in the brand’s collection for anyone who’d like to have the feeling of the 62MAS in a modernly produced watch. Except that with the SLA065, there’s more.

Seiko Prospex Diver Save the Ocean SLA065 Astrolabe Dial 62MAS-inspired

How to position this new model? While the SLA017 and SLA037 were faithful to the original 1965 model in terms of looks and proportions (not in size, though), this new SLA065 has to be considered the higher-end sister to the SPB series. It isn’t meant to be a vintage Re-Creation but a Modern Re-interpretation – this is how the brand positions its watch. It is inspired by the vintage watch but isn’t copying it entirely. It brings the flair of the past, just like the SPB series, with more refined elements, a case with more attention to details and a movement from a far higher range.

Seiko Prospex Diver Save the Ocean SLA065 Astrolabe Dial 62MAS-inspired

What does it mean in the metal? The Seiko Prospex Diver Save the Ocean SLA065 isn’t the same watch as an SLA017. The case is new and has different proportions. The diameter is 41.3mm, and the height is 13.1mm – thus substantially larger and thinner. Lug-to-lug distance is 47.6mm, which is relatively compact and makes it a watch that wears comfortably. Being part of the SLA series, this watch has more refinement in its materials and construction. The case is stainless steel but comes with a super-hard coating (a clear surface coating that practically doubles the scratch resistance of steel). Also, the finishing of the case combines brushed surfaces with Zaratsu (distortion-free) polished accents, a traditional technique employed by Grand Seiko.

Then, if you look at the SLA065 next to an SLA017 or an actual 62MAS, you’ll notice that the bezel is wider. Again, this changes the entire perception of the watch. A bit bulkier, a bit less retro, more robust and thus closer to the SPB series. The mood of the 62MAS is present, but not in the same retro way as it was in the past re-editions. After all, this watch is named Modern Re-interpretation. Talking about the bezel, the insert is not ceramic but metallic and coated in blue. Personally, I prefer the look and feel of a metallic insert compared to ceramic, even though the latter brings more durability. The bezel has a complete 60-minute graduation and rotates unidirectionally with 120 clicks.

Seiko Prospex Diver Save the Ocean SLA065 Astrolabe Dial 62MAS-inspired

All other features of this SLA065 are classic: a screw-down crown, a solid steel screwed caseback and an anti-reflective domed sapphire crystal on top (but not a box-shaped one as in the SLA017) and 200m water-resistance.

Seiko Prospex Diver Save the Ocean SLA065 Astrolabe Dial 62MAS-inspired

The dial is where the brand has been creative. First, this new model is part of the “Save the Ocean” series earmarked by the brand to foster a greater understanding and preservation of the world’s oceans with financial and other support to chosen marine charities. One of these is an underwater archaeology project, which explains the choice for the dial design. The texture is inspired by the astrolabe, an ancient navigational tool that seafarers used to determine the latitude and time of their location based on the position of the stars and the Sun to assist their navigation.Seiko Prospex Diver Save the Ocean SLA065 Astrolabe Dial 62MAS-inspired

I’m slightly sceptical regarding why the brand chose this pattern – and no, your SLA065 cannot be used as an astrolabe – but the result is visually pleasing and adds interest to the design. It’s a departure from the classic matte black or sunray-brushed blue dials we’re seeing on most watches. At least, in the present case, it is not too obvious; it remains discreet and doesn’t compromise legibility. As expected, the brand has featured large applied markers and hands, both generously filled with LumiBrite. Also, the hours and minutes hands are executed with a dual finishing; one side is brushed and the other polished, guaranteeing optimal contrast in all conditions. You’ll notice that, as with most recent Seiko dive watches, the SLA065 has a small luminous plot next to the date. Not the most elegant solution, but keep in mind that this is necessary to meet the ISO6425 standards.

Inside the case of the 62MAS-inspired Seiko Prospex Diver Save the Ocean is quite a nice movement, the calibre 8L35. This movement partially explains the higher-end positioning of this watch, as we’re talking about a calibre based on a Grand Seiko 9S55 ébauche. Developed explicitly by Seiko for its dive watches, it shares the same architecture and specifications as the GS movement, yet in a less decorated version with updates to make it more resistant to shocks. It beats at 4Hz, boasts 50 hours of power reserve, and features a SPRON (a Seiko alloy) hairspring, an escape wheel, and a pallet fork made with MEMS (Micro Electro Mechanical Systems) technology. Its accuracy is rated between +15 and -10 seconds/day – something that seems quite negative and could be improved by the brand, which should get closer to chronometer standards.

Seiko Prospex Save the Ocean 62MAS-inspired SLA065

The Seiko Prospex Diver Save the Ocean SLA065 comes equipped with a blue, striated silicone strap and a steel pin buckle. It is an excellent watch on the wrist, with good proportions – somehow the sweet spot for a vintage-ish diver. It’s not too thick, and the L2L is reasonable.

Seiko Prospex Diver Save the Ocean SLA065 Astrolabe Dial 62MAS-inspired

There is one thing that we clearly need to talk about: the price. Many comments have mentioned the EUR 3,000 price tag as exaggerated. Surely, it is higher than most of the watches produced by Seiko, but there are good reasons for this. First of all, an equivalent SLA017 of 2017 (and yes, in six years, the market has changed drastically) with an identical movement and nothing better in terms of finishing was priced at EUR 3,800 (which would have been easily 4.5 to 5k in 2023). The SLA037, with a hi-beat movement, was priced at EUR 6,500… The SLA065 is a very fine piece, far better finished than a watch from the SPB series, with a movement that has nothing in common with a 4Rxx or a 6Rxx, or with a Sellita or ETA. You can feel the difference when you handle and wear the SLA065. This watch isn’t cheap, but it has features that match its price. I do understand, however, that some of you will be reluctant to invest that amount of money in a Seiko.

Seiko Prospex Diver Save the Ocean SLA065 Astrolabe Dial 62MAS-inspired

The Seiko Prospex 1965 Diver’s Modern Re-interpretation Save the Ocean Limited Edition SLA065 is a limited edition of 1,300 pieces, which will be available from February 2023 at Seiko Boutiques and select retail partners worldwide. For more details, please visit

2 responses

  1. I really like this diver from seiko, it just looks the business. I must admit that I’m a seiko tragic. Would really like to add this one to my collection.

  2. The case is the same as on spb143, even the bracelet from spb143 fits perfectly on this one. The difference in the official specs is because bezel on the sla065 is bit wider than the case and the difference in height is due to the different crystal. So please do your homework before publishing misleading data. Cuz in your article you try to justify the price jump with SLA065 having new better case which is not true. So, only the movement and the crystal are new here, ok, this one is also limited but gosh there are so many limited editions coming form seiko that in the end it doesn’t really matter.

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