Monochrome Watches
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Grand Seiko Calibre 9SA5 now in Steel, with the SLGH003

GS' innovative movement with Dual Impulse Escapement, now available in stainless steel.

| By Brice Goulard | 4 min read |
Grand Seiko 60th Anniversary Limited Edition SLGH003 Calibre 9SA5 Dual Impulse Escapement Steel

While it has never been a secret that Grand Seiko was capable of crafting some of the finest and most precise luxury watches – pieces that are clearly on par with the best Swiss manufacturers – the concept of innovation at GS is less widely known. Recently, the brand unveiled a concept movement, the T0 Tourbillon Constant Force, a proper demonstration of savoir-faire. Also, Grand Seiko unveiled its Calibre 9SA5, an unprecedented escapement packed with innovations. First unveiled in gold, this powerful engine now comes in a stainless steel limited edition inside the new SLGH003.

Undeniably an attractive watch,  the SLGH002 was produced in a limited run of 100 watches and was cased in 18k making with a price tag of EUR 45,000; two factors that converted it into a highly limited and inaccessible watch. We knew back then that this watch was a showcase piece to announce the brand’s new calibre, the Hi-Beat automatic 9SA5.  With a revolutionary geometry for its escapement, the 9SA5 represents a whole new generation of Grand Seiko mechanical movements. Today, the brand unveils this engine in a far more accessible piece, now cased in steel.

Grand Seiko 60th Anniversary Limited Edition SLGH003 Calibre 9SA5 Dual Impulse Escapement Steel

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This new SLGH003 does not differ much from its gold counterpart in terms of design, as the case adopts the same proportions and shapes. As such, the watch has a 40mm diameter and a reasonable 11.7mm thickness, as well as a new overall design with a vertically brushed bezel, curved casebands and well-designed lugs with an alternation of brushed accents and (Zaratsu) polished facets. This watch is part of the Heritage collection, meaning that it reflects the past of Grand Seiko and is sportier, explaining why it is worn on a steel bracelet. The latter is equipped with a folding clasp, with a gold insert.

The hands and indexes on the dial of this new SLGH003 are also identical to its gold predecessor, which introduced a new design for GS. These are slightly bolder than usual and have a triangular profile with a central recessed line. The dial is sunray-brushed and executed in Grand Seiko blue, the colour of all watches in the 60th-anniversary collection. It features coloured accents: gold for the logo, red for the seconds hand.

Grand Seiko 60th Anniversary Limited Edition SLGH003 Calibre 9SA5 Dual Impulse Escapement Steel

Where the Grand Seiko 60th Anniversary Limited Edition SLGH003 truly differentiates itself from other, already well-powered GS models, is on the movement side. With the introduction of calibre 9SA5, the brand introduced its Dual Impulse, a brand new geometry for the escapement which differs from that used in the classic lever escapement. As you can see, the escape wheel has a star shape with 8 arms, instead of a wheel with teeth.

The main concept behind Grand Seiko’s Dual Impulse Escapement is that the locking and impulse functions are dissociated – a solution similar to the Audemars Piguet or the Omega Co-Axial escapements, for example. In one direction, power is transmitted directly to the balance (clockwise), as the roller receives impulse directly on its jewel. In the other direction, it receives an indirect impulse via the pallet fork, as in a traditional escapement. Thanks to this dissociation of the locking and impulse functions, with friction occurring in only one direction, the escapement is more efficient (less friction means less energy required) and more wear-resistant. Calibre 9SA5’s new escapement works in conjunction with a new free-sprung balance that is more resistant to shock and friction and retains its precision for longer periods.

Grand Seiko 60th Anniversary Limited Edition SLGH003 Calibre 9SA5 Dual Impulse Escapement Steel

This innovative escapement is used in a movement that is also entirely new. With a slimmer profile (5.18mm), more power storage (two barrels for 80h), a transversal bridge (for more resistance), and a high-frequency (5Hz or 36,000vph), the accuracy is rated at +5 to -3 seconds per day. The movement itself is also very pleasantly shaped and designed, with more appeal and superior decoration – bridges are nicely curved with polished bevels on the edges and more subtle wave patterns on the flat surfaces.

Availability and price

The Grand Seiko 60th Anniversary Limited Edition SLGH003 with Calibre 9SA5 will be a limited edition of 1,000 pieces. It will be available at Grand Seiko Boutiques and selected retailers worldwide as of December 2020 and priced at EUR 10,000.

More details at

3 responses

  1. Very nice watch and finally with an acceptable height (a frequent complaint with Grand Seiko’s watch range). Interesting movement as well and a gorgeous dial as is often the norm with GS. But why-oh-why again a limited version???? Can’t we just stop this LV nonsense which only serves to drive up the price The Richmont Group are also acknowledged experts in this field. GS’s management should make this watch watch widely available and reduce the price as a higher volume at a somewhat lower price point will increase revenue. Oh and whilst we are at this, can GS please make their Japan-only versions widely available in the rest of the world. Due to the Covid pandamic nobody will travel to Japan in the next few years.

  2. Owning several Seikos, including Spring Drive, GS, Astron and more you`re absolutely right. And there`s the ugly Prospex sign and generally exploding prices in the mid-upper segment.

  3. Lots of ??? for an otherwise fine watch. That gold insert on the folding clasp is hideous, and the etched logo on the rear glass seems to purposefully obscure the full view of the movement.

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