At Watches & Wonders 2024, Grand Seiko announced the new 9SA4 caliber and the first two watches featuring it, the SLGW002 and SLGW003. As a refresher, the 9SA4 is a manual hi-beat (36,000 bph), 80-hour, time-only caliber featuring their in-house dual-impulse escapement, first seen in the 9SA5. With a power reserve on the back of the movement, beautiful bridge designs and finishing, and a unique “wagtail-bird-shaped” winding click, it set a new bar for Grand Seiko’s mechanical calibers. But, perhaps just as exciting as the movement itself was that the watches featuring it were sized at an idyllic 38.6mm diameter and 9.95mm thickness with a 20mm lug, addressing the naysayer’s concerns around Grand Seiko’s sizing.

While a pair of fantastic releases, since introduction, we have been wondering where we will see this movement next. Well, we just got our answer, and I have to tell you, I’m equally surprised and delighted. They went vintage rather than with the new case and a different dial, which would have been most expected. Yes, they decided to bring back, as a limited edition, of course, a “recreation” of the 45GS from 1968. A little history, the 45GS came out a year after the 44GS and featured the same case design, but differed in that it featured the brand’s first hi-beat manual wound movement, the 4520.

The SLGW005 – the return of the 45GS

The 44/45GS case defines the Grand Seiko “Grammar of Design” as set out by Taro Tanaka, with flat, Zaratsu polished flanks, and an overall faceted shape that is unique to the brand. The DNA of these cases has persisted in the modern Grand Seiko collection, specifically in the 44GS Heritage models in 40mm and 36.5mm sizes, featuring nearly every movement Grand Seiko makes.

So, it would seem like a logical format to introduce the new 9SA4. It’s their icon, after all. However, rather than retrofitting the modern design to fit the new movement, as they did with the 9SA5, they created something new, or perhaps old. Labeled the SLGW005 and SLGW004, these vintage throwbacks feature a visually accurate recreation of the original 44/45GS case, though with slightly different dimensions.

The SLGW004 – Grammar of design in gold

Coming in at 38.8mm in diameter and 10.4mm thick with 19mm lugs, they are a marginally upscaled version of the original design that brings back a detail lost on modern models: connected lugs. A slight difference that has a significant impact (and is a personal favorite detail), this extra material between the lugs transforms the design, making it a bit dressier, and more distinctive. This detail hasn’t been seen since a series of similar limited editions from 2013.

However, the recreation isn’t limited to the case, with the dial staying faithful to the originals, including in some surprising ways. The needle hands, faceted applied markers, and simple printed minute/seconds index appear accurate but are also fairly standard on modern GS watches. What’s unexpected and makes these LEs particularly special is the branding and dial text.

Only “Seiko” appears below twelve, as it did from 1960 to 2017, when Grand Seiko became its own brand under the Seiko Corporate umbrella. Only the letters “GS” appear on the dial above six. I was surprised to see this for a couple of reasons. First, the rebrand was a conscious effort to put some distance between Seiko and Grand Seiko, given the latter’s luxury aspirations. Second, given that the 9SA4 is so new, this seems to downplay its position as one of their highest-end movements. With that said, I love that aspect of it in particular.

Additionally, above six, along with “hi-beat” and “36000,” is a curious little lightning bolt/S-shape that in 1968 would have indicated that the watch was made in the Daini Seikosha factory. This is a very cool easter egg that, apart from being accurate to the 45GS, feels particularly tuned to Grand Seiko nerds, as it’s not been present on a dial in a long time, including on the 2013 LEs.

Daini Seikosha logo at 6

One departure from the 1968 original, as well as the 2013 version, is that Grand Seiko opted for a display case back instead of a solid with GS emblem/coin. While this might irk the purists, I think it’s both understandable and, to my tastes, preferable. While all Grand Seiko movements have their charms, the 9SA4 is particularly attractive and well-designed. Also, what good is a movement-side power reserve if it’s hidden?

So, if you are like me, then you’re wondering why Grand Seiko is making a 45GS-inspired limited edition right now, as 2024 is not an anniversary of 1968. The answer, it would seem, is because of the 9SA4. The 4520 from 1968 was the brand’s first hi-beat manual wound movement, and the 9SA4 is the first of the modern era. Though Grand Seiko has had hi-beat automatics for a long time by way of the 9S85, there never was a manual variant.

The stunning 9SA4 caliber

In terms of the models, the SLGW005 is steel with an off-white dial, silver markers, and hands. It comes on a stitchless black crocodile strap with a vintage-styled Seiko buckle. It is priced at $9,700 and limited to 1200 pieces. The SLGW004 is solid 18k yellow gold, also with an off-white dial, but with gold markers and hands. It features the same strap with gold buckle, is priced at $30,000 and limited to 200 pieces. Both models will be available beginning in November of 2024. Grand Seiko