Grand Seiko Updates its Classic Evo9 Collection Models with Spring Drive UFA Calibre and a New Bracelet

Just a couple of hours ago, we introduced one of Grand Seiko‘s new models for 2026, the Spring Drive UFA 40mm Lake Suwa SLGB007. And yes, we decided to give this model its own dedicated article, being a new reference in the Evolution 9 collection. However, there is more coming from Japan… Grand Seiko has indeed decided to revamp several of its most emblematic models, whether Spring Drive or mechanical watches. And we start now with the SLGB009 White Birch, SLGB011 Atera Valley, SLGB013 Lake Suwa, three watches with names that must feel familiar to our regular readers. But beneath the well-known designs, both the movement and the bracelet have received a strong update. 

What we’re looking at now are evolutions of three existing watches: the White Birch SLGA009, the Atera Valley SLGA025 and the Lake Suwa SLGA007. All of these watches have been strong sellers for the brand and instrumental to its recent success. Based on the Evolution 9 style, all three were powered by the proprietary Spring Drive technology and the calibre 9RA2, a movement that marked a substantial upgrade over previous movements, such as the 9R6x architecture. But Grand Seiko decided to give these models some upgrades, mechanically and in terms of comfort.

First, all three references are now housed in an Ever-Brilliant Steel case – note that the Atera Valley SLGA025 was made of titanium. The case retains the classic 40mm diameter of the collection. This sharp, more ergonomic case with a box-shaped sapphire crystal is 0.1mm thinner here (due to the movement inside) and retains a sub-48mm lug-to-lug measurement. Water-resistance is rated at 100m thanks to a screw-down crown and screwed caseback. And GS chose to have the case and bracelet made from Ever-Brilliant Steel, which offers a better sheen and greater scratch resistance.

As for the dials, no evolutions to be found. The new SLGB009 White Birch, SLGB011 Atera Valley, and SLGB013 Lake Suwa retain everything that made the White Birch SLGA009, the Atera Valley SLGA025, and the Lake Suwa SLGA007 popular, respectively: a silvery-white dial with a wood-like effect, an emerald-green water-like pattern, or the all-time classic Lake Suwa pattern.

So what really changes, then? First, the bracelet. On previous models, many complained that the bracelets were too wide or not tapered enough, and that there was no adjustment to the clasp. Equally made from Ever-Brilliant Steel, the new bracelets of the SLGB009, SLGB011 and SLGB013 offer a greater degree of tapering than in previous models, making them both more pleasant to look at and to wear. Second, following its introduction on the Spring Drive UFA SLGB001 & SLGB003, these new models adopt a three-step micro-adjustment clasp, enabling precise, tool-free adjustments in 2mm increments for enhanced wearing comfort.

Then the movement. All three references replace the 5-day power reserve calibre 9RA2 with the newest, even more precise Spring Drive Calibre 9RB2, also known as Ultra Fine Accuracy. Capable of an impressive ±3 seconds per month accuracy (or ±20 seconds per year), this movement is smaller and thinner, measuring 30mm in diameter and 5mm in thickness. This automatic Spring Drive engine relies on a single barrel, which delivers a comfortable power reserve of 72 hours (with a nicely integrated indicator on the back). The open back reveals the Shinshu Watch Studio’s signature finishing, with frosted plates and bridges that contrast with the polished bevelled edges.

Released as part of the permanent collection, the Grand Seiko Evolution 9 Collection Spring Drive UFA 40mm SLGB009 White Birch, SLGB011 Atera Valley, and SLGB013 Lake Suwa will be available from September 2026 and priced at EUR 10,400. For more details, please visit www.grand-seiko.com.