The new Steel and Purple Dial Grand Seiko Spring Drive UFA Ice Forest SLGB005

Earlier this year, at Watches and Wonders Geneva 2025, Grand Seiko unveiled a new and rather important collection, fitted with a brand new movement and carrying a meaningful name, the Spring Drive UFA. Now, if you’re a GS fan, you’ll immediately spot the connection with the VFA models of the past, as the new Ultra Fine Accuracy movement pays tribute to the 1969 Very Fine Adjusted timepieces. Released as a pair of Ice Forest-themed models, the SLGB001 and SLGB003, this elegantly compact watch, with daily practicality, now comes back in a limited edition, the Spring Drive UFA Ice Forest SLGB005. Combining an Ever-Brilliant Steel case and a gradient purple dial, it has undeniable visual and mechanical appeal, but misses one of the great new features of the titanium SLGB003…

As explained in our first hands-on session with the new members of the Grand Seiko Evolution 9 collection, the UFA (Ultra Fine Accuracy) acronym was a nice tribute to the past. It refers to VFA or Very Fine Adjusted. First used in 1969, this designation defined a mechanical Grand Seiko watch that was adjusted so skillfully that it achieved an astonishing monthly rate of ±1 minute. Even by today’s standards, it is still impressive and competes with Rolex’s Superlative Chronometer’s claimed accuracy. But now, we’re in 2025, and Grand Seiko has a proprietary technology named Spring Drive, a sort of hybrid between mechanical and quartz that has the ability to go way beyond traditional ranges of accuracy claimed for mechanical movements. And this Ultra Fine Accuracy calibre 9RB2 is at the top of the game when it comes to being precise. More on that later.

Steel case and purple dial

First, let’s look at the design and style of this new Spring Drive UFA Ice Forest SLGB005. At first, not much has changed compared to the titanium SLGB003. The shape and finish of the case are identical, with this modern interpretation of Grand Seiko’s Grammar of Design, typical of the Evolution 9 collection. The case combines brushed surfaces with Zaratsu polished accents in a contemporary way, with a thin bezel, angular (but not too much) surfaces and a comfortable 100m water-resistance. The crown screws down, and the caseback features a sapphire crystal.

But like the titanium edition, what matters with this Ice Forest SLGB005 is the size… Elegant, casual, the case is 37mm in diameter and 44.3mm in length. And yes, the 11.4mm thickness is an improvement compared to many other GS watches, but I could live with 1mm less. Another important element of this new limited edition is the material, as the SLGB005 switches from titanium to Ever-Brilliant Steel (EBS), a brighter alloy that also has more corrosion resistance, with a PREN rating 1.7 times higher than classic stainless steel. This is GS’s answer to 904L steel, if you want. The use of EBS has two immediate consequences, and actually two benefits for me; it’s brighter in colour and has more sheen than titanium, which is like, and it’s heavier too, making the wearing experience more comfortable – or should I say more in line with my personal tastes (I prefer watches with a bit of heft, specifically on compact models).

The inaugural titanium and platinum models were equipped with light-toned dials (silvery-blue and ice blue, respectively) and introduced another nature-inspired pattern, the so-called Ice Forest texture, depicting the tips of frost-covered trees during winter months. Now, the Spring Drive UFA SLGB005 adds the idea of seeing these at dawn, with a gradient purple colour over its fine texture. The colour is subtle, which is for the best. It is present enough for the wearer to notice it, but not too much so that it remains discreet. All elements of the dial are here silver-toned, with the bold hands and grooved hour markers of the Evolution 9 collection.

The UFA Calibre 9RB2

Inside the case is the same calibre 9RB2 that was initially presented within the Titanium SLGB003. Using the Spring Drive technology, the objective of this movement was double: compact and thin to deliver new, sleeker watches, and also more precise than anything done before by the brand (in fact, it is the most accurate wristwatch movement powered by a mainspring today). The 9R6x generation of movements was capable of ±15 seconds per month. The Calibre 9RA5 presented in 2020 upgraded the monthly accuracy to ±10 seconds. The new Ultra Fine Accuracy calibre 9RB2 pushes the limit to an impressive ±3 seconds per month (or ±20 seconds per year), an accuracy that many purely mechanical watches can’t even reach on a daily basis. The process to achieve such precision is explained here.

For the rest, the movement remains identical in this purple SLGB005, 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 an indicator nicely integrated on the back). The open back reveals the signature finishing of the Shinshu Watch Studio, with frosted plates and bridges bringing contrast to the polished bevelled edges.

Steel bracelet, no more micro-adjustment

As you can expect, the bracelet of this new purple limited edition, if identical in style, matches the case’s material and is made of Ever-Brilliant Steel. However, something is missing compared to the titanium edition… When this watch was presented, not only did it feature a new movement but also came, to our great surprise and pleasure, with (finally…) a micro-adjustment system on the clasp. Sadly, this comfort-release device is no longer present on the steel SLGB005, which moves back to a traditional three-fold clasp (with an 18k gold medallion) with push-button release… Too bad, as for the rest, this new edition is brilliant in every aspect.

Availability & Price

The new Grand Seiko Evolution 9 Spring Drive UFA Limited Edition SLGB005 with purple dial will be available worldwide in November 2025 and will be produced in 1,300 pieces. It will be priced at EUR 11,000. For more details, please visit www.grand-seiko.com.