Imagen: Grand Seiko, web oficial
The storyWhy this reference matters
February 2023. The SLGA021 is the catalogue version of an idea that had appeared two years earlier as a limited edition, the SLGA007. Same lake relief, a considerably deeper blue, and none of that one's gold touches. Grand Seiko does this often: try a dial in a short run and, if it works, make it permanent in another shade and drop the numbering.
The subject is Lake Suwa before dawn, when the wind barely ripples the water and it's still dark. The lake sits close to the Shinshu Watch Studio at Shiojiri, where every Spring Drive in the house is built: it is literally the landscape the people assembling the watch look at. In low light the blue goes almost black and the relief disappears; under raking light it comes back whole.
The calibre 9RA2 is the long-running generation of Spring Drive: 120 hours of reserve, ±0.5 seconds a day — ±10 a month — and 38 jewels. It measures the temperature 540 times an hour to correct drift in the quartz acting as reference, and it uses barrels of different sizes and an offset Magic Lever to save height. All of which keeps the movement to 5 mm and the case to 11.8.
SpecificationsThe numbers, in one table
| Brand | Grand Seiko |
|---|---|
| Family | Evolution 9 |
| Reference | SLGA021 |
| Years made | desde 2023 |
| Calibre | Grand Seiko 9RA2 |
| Movement | Spring Drive |
| Power reserve | Aprox. 120 horas (5 días) |
| Jewels | 38 |
| Complications | Fecha · Indicador de reserva de marcha (en el fondo) |
| Diameter | 40 mm |
| Thickness | 11.8 mm |
| Lug to lug | 47.9 mm |
| Lug width | 22 mm |
| Case | Acero inoxidable |
| Crystal | Zafiro de doble curvatura con tratamiento antirreflejos |
| Water resistance | 100 m (10 bar) |
IdentificationHow to tell it apart
The first thing to notice is what isn't there: no power reserve indicator on the dial. Earlier automatic Spring Drives, starting with the Snowflake, carry theirs at eight and eat a section of dial. Here it has moved to the back, which also shows the Shinshu Frost decoration. All that's left on the front is the date at three, in a bevelled frame.
Steel case, 40 mm, 47.9 lug to lug, 11.8 thick and 22 mm lugs, on a five-link bracelet. Against the Snowflake SBGA211 — titanium, white, 72 hours — this one is heavier in the hand, blue, and gives you five days. The check takes a glance: if there's a power reserve on the dial, it isn't an SLGA021.
Against the limited SLGA007, the 021's blue is noticeably darker and it has none of that one's gold detailing. And the seconds hand, as on every Spring Drive, glides without a single step: if it shudders or moves in tugs, either it isn't a Spring Drive or there's a problem inside.
CollectingWhat collectors check
Wind it fully — or wear it for a couple of days — and check on the back that the indicator reaches the top and that the watch really does hold five days. A Spring Drive that dies at ninety hours has a tired mainspring, if not something worse.
Servicing always goes through Seiko's official network: inside there's an integrated circuit, a coil and a glide wheel, and those aren't parts you find loose. Ask when it was last serviced and keep the paperwork, which counts for a lot at resale on a catalogue model.
The relief dial cannot be restored, so go over it under raking light looking for marks or dust beneath the crystal. And on the bracelet, check the side play in the links and that every link is still there: Grand Seiko spares aren't available round the corner.
Common questionsWhat people ask us about this reference
How long does the SLGA021's power reserve last?
A hundred and twenty hours — five full days — with the 9RA2 fully wound. The indicator isn't on the dial: you read it through the display back.
How is it different from the SLGA007?
The SLGA007 was a 2021 limited edition with the same lake relief but in a lighter blue and with gold detailing. The SLGA021 is a catalogue model and its blue is far deeper.
Is it more accurate than an ordinary mechanical watch?
Considerably: ±0.5 seconds a day against the +5/−3 of a mechanical from the same brand. Spring Drive uses a quartz as its reference, even though all the energy comes from the mainspring.
Does it have a battery?
No. The current feeding the regulator is generated by the mainspring itself as it unwinds. There is nothing to replace every few years.
Keep readingWhere to go from here
Close relativesThe ones it gets confused with
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