This Grand Seiko is one of the most accurate watches we've ever seen

Grand Seiko has revealed what it claims to be the most accurate mainspring-powered watch ever made at Watches and Wonders.

Called the SLGB003 and part of the new Evolution 9 Collection, the titanium watch is driven by a new movement called the Caliber 9RB2. Whereas most watches are stated as being accurate to between about two and six seconds, plus or minus, per day, Grand Seiko says its new movement is accurate to plus/minus 20 seconds per year.

To spell that out – because, frankly, we think it needs reiterating – the new Grand Seiko Evolution 9 and its 9RB2 movement will gain or lose just 20 seconds over the course of an entire year. That’s about 0.05 seconds per day, or about 1.7 seconds per month. Remarkable stuff, we think you’ll agree.

The Japanese watchmaker says how its movement has received the new UFA designation, standing for Ultra Fine Accuracy. Grand Seiko adds: “The groundbreaking movement boasts a level of precision defined not by accuracy in seconds per day, week, or month, but by its accuracy over one year.”

As for the watch itself, Grand Seiko says how the icy texture and colouring of the dial was inspired by the frost-covered trees of the Kirigamine Highlands to the east of the Shinshu Watch Studio, where spring-driven Grand Seiko watches are made.

The company says of the dial: “The intricately textured dial captures the beauty of those ice forests thanks to finishing techniques that create pale blue tones that are subtle yet striking in their presence.”

That dial sits within a 37mm titanium case topped by a box-shaped sapphire crystal and with an exhibition case back for viewing the movement and its power reserve indicator. Water resistance is 100 metres, and as well as being supremely accurate, Grand Seiko says the new automatic movement has a power reserve of 72 hours. The watch is presented on a three-link bracelet with a three-fold clasp with push-button release and micro-adjustment function.

Available now, the Grand Seiko SLGB003 from the new Evolution 9 Collection is £9,950.