In a world where precision is a requirement, Grand Seiko relentlessly pursues its quest. True to its tradition of going further, the Japanese manufacture presents this spring 2025 an exceptional double creation: the Spring Drive U.F.A. (Ultra Fine Accuracy), references SLGB001 and SLGB003, genuine technological showcases of what the Shinshu Watch Studio can produce at the height of its art. More than a tribute to history, this marks a major milestone in the history of the absolute measurement of time.
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Annual precision: the advent of the caliber 9RB2
The heart of this feat beats to the rhythm of the Spring Drive 9RB2 caliber, an automatic movement that inaugurates the new U.F.A. – Ultra Fine Accuracy designation. Where the majority of calibers are measured in seconds per day or per month, this one operates in another dimension: ±20 seconds per year, making it the most precise spring-driven movement ever produced to date according to the manufacture’s data.
This level of performance is the result of several years of research on the quartz oscillator used in the Spring Drive system. Aged for three months, measured at various temperatures, then thermo-compensated thanks to a very low-consumption integrated circuit, the oscillator is then vacuum-sealed with its sensor, shielded from electrostatic aggression, humidity and light. Grand Seiko goes even further: this 9RB2 caliber is the first to incorporate a regulation switch, allowing the watchmaker to adjust long-term precision during service operations. Extreme care is thus given to the stability, reliability and longevity of timekeeping.
Design Evolution 9: form serving function
This technicity unfolds within a case 37 mm in diameter, the smallest ever paired with a 9R series Spring Drive movement. The Evolution 9 collection offers here a showcase of elegance, drawing on the strong lines introduced by the 44GS reference in 1967: sharp bevels, distortion-free Zaratsu polishing, contrast of polished and brushed finishes, sculpted hands and prominent indexes for optimal legibility.
Wearing comfort is not left behind. The lowered center of gravity, the widened and perfectly balanced bracelet, as well as a tool-free micro-adjustment clasp for the titanium version, ensure an ideal fit, true to Japanese ergonomics where detail always takes precedence over effect.
Poetry of ice: two dials inspired by Kirigamine
The dials, for their part, draw their inspiration from the winter landscapes of Kirigamine, a region neighboring the Shinshu Watch Studio. During the frozen months, the frost-covered trees there create a hypnotic spectacle. It is this atmosphere that Grand Seiko captures through complex textures in bluish hues.
The SLGB003 model in High-Intensity Titanium features a silvery-blue dial, with vivid and crystalline reflections, punctuated by a blued seconds hand. The SLGB001 version in platinum 950 opts for a slightly deeper blue, crossed by a steel glide motion seconds hand, the aesthetic signature of the Spring Drive. Both dials proudly bear the inscription “SPRING DRIVE UFA” at 6 o’clock, in direct reference to their extreme precision.
Movement finishing and mechanical poetry
Through the sapphire case back, the 9RB2 caliber reveals a finish inspired by the snowy landscapes of Shinshu. The rubies recall the stars of winter nights, while the mirror-polished surfaces and beveled edges return light like the frost crystals on the branches of the forests. A deeply Japanese aesthetic, made of restraint, harmony and textures.
A timepiece for purists
The platinum model (SLGB001) is offered as a limited edition of 80 pieces, exclusively in Grand Seiko boutiques. It is fitted on a crocodile strap with a platinum clasp and 18 ct white gold elements. The SLGB003 version in high-intensity titanium will for its part be distributed through a broader network, with a metal bracelet and micro-adjustment clasp. The indicative prices are set at €42,000 for the platinum model and €12,000 for the titanium version.
Precision as an absolute
With the Spring Drive U.F.A., Grand Seiko crosses a new threshold, where extreme precision is no longer an ambition, but a reality. This creation embodies what Japanese watchmaking does best: the union of technological rigor, aesthetic refinement and a deep respect for nature and time. At the dawn of its future, the house of the Shinshu Watch Studio asserts that time can be more than an indicator: it can be a horological work of art, at the perfect rhythm.
Frequently asked questions
U.F.A. stands for Ultra Fine Accuracy. It is a new designation inaugurated by Grand Seiko with the Spring Drive 9RB2 caliber, which guarantees a precision of ±20 seconds per year — according to the manufacture, the most precise spring-driven movement ever produced to date.
The Spring Drive is a watchmaking system developed by Grand Seiko that combines a classic automatic mechanical movement with a mainspring and a thermo-compensated quartz oscillator. It is this electronic regulation that enables the glide motion seconds hand, the aesthetic signature of the Spring Drive, and a level of precision inaccessible to purely mechanical escapements.
The 9RB2 caliber displays a precision of ±20 seconds per year. The quartz oscillator is aged for three months, measured at various temperatures, thermo-compensated, then vacuum-sealed with its sensor. The caliber also incorporates an unprecedented regulation switch allowing the watchmaker to adjust precision during service operations.
The indicative prices are €42,000 for the SLGB001 in platinum 950 and €12,000 for the SLGB003 in high-intensity titanium.
The SLGB001 in platinum is offered as a limited edition of 80 pieces, exclusively in Grand Seiko boutiques. The SLGB003 in high-intensity titanium benefits from a broader distribution, on a metal bracelet with a micro-adjustment clasp.
