Description
About Grand Seiko SLGB001
Grand Seiko Spring Drive U.F.A Evolution 9 Collection
The Spring Drive U.F.A. movement with an astounding annual rate makes its debut in a limited edition inspired by the beauty of ice forests
The pursuit of high accuracy has been the cornerstone of Grand Seiko’s values since its first watch was created in 1960. In the late 1970s, the development of Spring Drive began with an aim to harmoniously blend the traditional energy of a mainspring with state-of-the-art electronic watchmaking advancements. In 2004, Grand Seiko introduced the Spring Drive Caliber 9R65 with a monthly rate of ±15 seconds.
Today, this legacy of accuracy in watchmaking reaches new heights with the announcement of the Spring Drive Caliber 9RB2, which receives the new U.F.A. designation, standing for “Ultra Fine Accuracy.” 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. The automatic U.F.A. movement has an astounding annual rate of ±20 seconds, making it the most accurate wristwatch movement powered by a mainspring today.*
*As of April 2025, based on Grand Seiko’s research.
In 2025, the Caliber 9RB2 makes its debut in the Evolution 9 Collection. To the east of the Shinshu Watch Studio lie the Kirigamine Highlands, where frost-covered trees can be observed during harsh winter months. The intricately textured dial captures the beauty of these ice forests thanks to finishing techniques that create pale blue tones that are subtle yet striking in their presence. This limited edition watch features a Platinum 950 case and a crocodile strap.
Limited edition of 80 pieces.
About Spring Drive
Spring Drive is Seiko’s exclusive movement that achieves an unprecedented level of accuracy (+/- 15 seconds per month on average, equivalent to +/- 1 second per day) by regulating a spring-driven watch with state-of-the-art electronic technology that functions without batteries or other external power source.
As in conventional mechanical watches, the sole power source of Spring Drive is a mainspring that can be wound by the motion of an oscillating weight or by winding the crown. And just as in mechanical watches, the mainspring drives a series of gears that rotate the hour, minute and second hands. A rotor, connected to the end of these gears, generate a small electrical charge that activates an electronic circuit and quartz oscillator.
The Tri-synchro regulator is a unique speed controller for Spring Drive that replaces the escapement, which is a mechanical speed control device used in almost all conventional mechanical watches. The Tri-synchro regulator moves the second hand in a smooth motion, without ticking and with extreme accuracy.
Some 80% of the components in a Spring Drive caliber are the same as those in a luxury mechanical watch. Spring Drive is a movement powered by a spring, just like a mechanical watch, with a different kind of regulator and combines the long-lasting autonomy of a mechanical watch with the precision that, until now, only electronic watches could provide.
To ensure reliable and accurate operation, all these parts need to be manufactured to the highest standards of precision, and assembling them requires superior craftsmanship.
The development of the Spring Drive movement caliber 9R was made possible because Seiko is one of the very few manufactures with expertise in both mechanical and quartz watches.
Since the first Grand Seiko Spring Drive in 2004, new movements have been created with even more complex mechanisms–including the GMT in 2005 and chronograph with GMT in 2007. Showing that with the Spring Drive caliber 9R, time never loses momentum.
Grand Seiko SLGB001 Features
Astonishing accuracy
The new movement achieves its ±20-seconds-per-year accuracy thanks to new and enhanced manufacturing and processing methods for the three-month-aged quartz oscillator, and a newly designed IC. And, as with the 9RA series of Spring Drive movements, the frequency of each individual quartz oscillator is measured at several different temperatures, with the resulting data necessary for thermo-compensation programmed into the low-power IC. Both the oscillator and sensor are vacuum-sealed to minimize temperature differences and protect against external factors such as humidity, static electricity, and light, ensuring precise temperature adjustments and the stable performance of the quartz oscillator. In addition, for the first time in Spring Drive, the new movement features a regulation switch that can be used during after-sales service to correct any divergences in accuracy that may occur over long periods of use.
Dial inspired by the ice forests
This creation features a blue dial with pressed pattern inspired by the beauty of these ice forests, offering a refined backdrop to the seamless glide motion of a silver-colored seconds hand. Thanks to the movement’s compact design, the new watches have a case diameter of just 37mm, making them the smallest models powered by the 9R series to date and ideal for smaller wrists.
Movement finishing reflecting the natural beauty of Shinshu
The movement’s beauty is revealed through the sapphire crystal case back, with mirror-polished, beveled edges adding brilliance. Its design, inspired by the natural surroundings of the Shinshu Watch Studio where it is made, reflects a uniquely Japanese aesthetic characterized by understated charm and elegance. The jewels echo the glittering stars that sparkle during the early days of winter above the surrounding mountains, and the delicate texture of the movement’s surfaces reflects the frost that winter brings to the trees of Shinshu, where all Grand Seiko Spring Drive watches are made.
The Spring Drive U.F.A. caliber with an astounding annual rate
The pursuit of high accuracy has always been the cornerstone of Grand Seiko’s values. Receiving the new U.F.A. designation, which stands for “Ultra Fine Accuracy,” Caliber 9RB2 boasts a level of precision defined not by accuracy in seconds per day, week, or month, but by accuracy over one year. The movement has an astounding annual rate of ±20 seconds, or approximately ±3 seconds per month.
- 34 jewels
- LIMITED EDITION on the case back
- Serial number engraved on the case back
- Platinum 950 clasp (partly 18k white gold)
- Case back with lion emblem
- Date display
- Power reserve indicator
- Screw case back
- Screw-down crown
- See-through case back
Grand Seiko SLGB001 History
Prior to 1960, to challenge the status of Swiss watches and change the perception of Japanese watches, Daini Seikosha and Suwa began the discussion of a product line that can match the quality of Swiss watches under the suggestion of the parent company. At the time, Suwa Seikosha Co. was in charge of manufacturing men’s watches, so it was decided that Suwa would be producing the first Grand Seiko (GS).
The first Grand Seiko was released in 1960, it was based on Seiko’s previous high-end watch, CROWN. This Grand Seiko has a 25-jewel, manual-winding, 3180 caliber, and only 36,000 units were produced. This was also the first chronometer-grade watch manufactured in Japan, and it was based on Seiko’s own chronometer standard.
Design style
The design language of the Grand Seiko was set in 1967, with the creation of Grand Seiko 44GS. The 44GS set the ground for all future Grand Seiko with nine elements. These elements help improve the legibility of the watch under different situations, and create a sharp, crisp visual impression:
- Double width index at 12 o’clock
- Multi-faceted rectangular markers
- Highly polished bezel
- Highly polished planes and two-dimensional surface
- Half recessed crown
- Flat dial
- Multi-faceted hour and minute hands
- Curved side line
- Reverse slanted bezel wall and case side
- Dress style with simple but beautiful design
- Zaratsu polishing
source : wikipedia
