Grand Seiko Introduces Spring Drive Ultra Fine Accuracy SLGB003

Grand Seiko produces the most precise hybrid mechanical timepiece featuring the Spring Drive Ultra Fine Accuracy (U.F.A) SLGB003.

Grand Seiko is a brand established on the principle of excellence. At one time, it epitomized the pinnacle of Seiko's watchmaking, envisioning the essence of a luxury Japanese timepiece. Today, it has evolved into an independent organization, maintaining the spirit of producing exceptional luxury Japanese timepieces with unparalleled craftsmanship. Moreover, there exists an ongoing pursuit by Grand Seiko to attain the highest standard of timekeeping accuracy. This year signifies the brand's advancement with the introduction of the Spring Drive Ultra Fine Accuracy (U.F.A) SLGB003.

Grand Seiko's Spring Drive technology aims to merge the accuracy of a quartz oscillator with the essence of mechanical timekeeping. It was conceived during a period when quartz movements were revolutionizing the industry, and by 2004, when it was initially revealed, the world was prepared to embrace mechanical timekeeping as a symbol of luxury.

The fundamental concept of the Spring Drive mechanism is that it use a mainspring to drive a geartrain, similar to any mechanical timepiece. The distinction is in the utilization of a quartz oscillator and a brake mechanism, rather than a conventional escapement system, to regulate the power release from the mainspring, allowing the seconds hand to move seamlessly and complete one full circle of the dial in 60 seconds.

In comparison, a chronometer certified by COSC must maintain an accuracy of -4/+6 seconds per day, whereas Rolex achieves an accuracy of -2/+2 seconds per day for its Superlative Chronometer. Spring Drive surpasses that with a variance of -10/+10 seconds per month. With the U.F.A., Spring Drive can achieve an accuracy rate of -20/+20 seconds annually. Indeed, annually! That equates to 3 seconds monthly and approximately 0.1 seconds daily. The Spring Drive U.F.A. is the most precise wristwatch powered by a mainspring to date.

To attain this remarkable precision, the calibre 9RB2 movement integrates a newly engineered integrated circuit (IC) with a quartz oscillator aged for three months. Similar to the preceding generation of Spring Drive movements, the frequency of each quartz oscillator is assessed at various temperatures, and the data is integrated into a temperature adjustment algorithm within the low-power integrated circuit.

The complete assembly is subsequently vacuum sealed to safeguard against external influences, including humidity, static electricity, and light. To achieve such precise precision, the new calibre 9RB2 is equipped with a regulation switch that after-sales technicians can utilize to rectify any discrepancies in accuracy.

In addition to its remarkable movement, the looks of the Spring Drive U.F.A watch possess a distinctive allure. Initially, it has a diameter of 37mm, rendering it the smallest case size to incorporate a 9R movement to date. The case and bracelet of the SLGB003 are constructed from High-Intensity Titanium, a challenging endeavor given that all Grand Seiko casings include some variant of Zaratsu mirror-polished surfaces. This remarkable pattern, not to overlook the dial, draws inspiration from the Kirigamine Highlands, located east of the Shinshu Watch Studio, where frost-laden trees rise majestically throughout the severe winter months.