Among Grand Seiko's new releases for 2026, watch writer Shinichi Sato takes a deep dive into the "Heritage Collection Caliber 9F 33mm," which features Grand Seiko's renowned 9F quartz movement housed in a 33mm diameter case. The case size of this model was made possible by the introduction of the Cal.9F51, the smallest 9F quartz movement available, and it's noteworthy that the design is universal, fitting well for both the writer, who has a relatively thick wrist compared to the average Japanese person, and for women.
Text by Shinichi Sato
[Article published on January 14, 2026]
A new model featuring the 9F quartz movement has been released, with the smallest case size at 33mm.
This feature delves into some of the most noteworthy models from Grand Seiko's 2026 new releases. This time, we'll be looking at the "Heritage Collection Caliber 9F 33mm." As the name suggests, this model features Grand Seiko's proud 9F quartz movement and comes in a 33mm case. In this article, we'll review the capabilities of the 9F quartz movement and explore the impression this model gives off due to its 33mm diameter.
The power of Grand Seiko's proud 9F quartz movement
The 9F quartz movement is a lineage of movements that originated with the Cal.9F83, which debuted in 1993. The Cal.9F83 aimed to be the "ultimate quartz" and "quartz that surpasses quartz," and was developed by combining the technologies of mechanical and quartz movements cultivated over many years, incorporating many new mechanisms that are still used today. Here, let's take a look back at the technical characteristics of the 9F quartz movement.
① Ultimate precision
The quartz crystal oscillator, the heart of a quartz watch, is made from quartz, a stable material, but slight individual differences are unavoidable, and these can become apparent over time. These individual differences can cause errors in the watch. Therefore, the quartz crystal oscillators used in the 9F quartz movement undergo a three-month aging process after processing, and only those that meet the standard and achieve stable accuracy are used. Furthermore, even with such meticulous and time-consuming production, individual differences are unavoidable, so the 9F quartz movement incorporates information about these individual differences into the control IC, resulting in even more accurate operation.
The high-precision operation achieved in this way is, however, limited to certain temperature conditions. Quartz has the characteristic of its vibration frequency drifting with temperature changes. Therefore, the 9F quartz movement senses the internal temperature 540 times a day and automatically corrects for temperature drift. This minimizes the impact on accuracy from putting on and taking off the watch, moving between indoors and outdoors, and temperature changes due to seasonal changes.
Furthermore, it features a regulator switch, which is not typically found in standard quartz movements, allowing for correction of errors due to long-term use and adjustment to suit the user's preferences.
② A "twin pulse control motor" that precisely drives the thick, heavy needle.
The "Grand Seiko Style," the design code for Grand Seiko watches, includes straight-shaped indices and dauphine-shaped hour and minute hands with multifaceted diamond cuts. This is a traditional design inherited from the first Grand Seiko and is an important element that defines the look of the watch. However, because the thick hands are heavy, they can be driven by powerful mechanical watches, but are difficult to incorporate into typical quartz movements.
In contrast, the 9F quartz movement increases output torque while using a "twin-pulse control motor" to stably drive the thick, heavy hands that are essential to the design. While typical quartz movements move one step per second, the 9F quartz movement has a mechanism that moves two steps per second, achieving both high driving force and energy efficiency.
③ Mechanism that produces stable needle movement
In addition, the 9F quartz movement incorporates mechanisms to ensure stable and smooth movement of its thick, heavy hands. One such mechanism is the "three-axis independent guide structure," which prevents the axes on which the hour, minute, and second hands are mounted from interfering with each other, allowing each to rotate independently and achieve smooth movement. This also enables the precise time setting that is essential for an accurate timepiece.
Another feature is the "backlash auto-adjustment mechanism." While gears need some play (backlash) to function, this play can cause the second hand to tremble. The backlash auto-adjustment mechanism suppresses this tremor by incorporating a hairspring, the heart of a mechanical watch, inside. The repulsive force generated by the hairspring stabilizes the movement of the second hand. This is a feature that only Grand Seiko, with its high level of technical expertise in mechanical watches, could achieve.
A 33mm model equipped with the highly refined 9F quartz movement has been realized.
There is still much to say about the 9F quartz movement, but let's move on to a deeper look at the new models. The 33mm case styling of the new Heritage Collection Caliber 9F 33mm models, Ref. SBGX359 and Ref. SBGX361, was made possible because the new Cal. 9F51 movement was developed, based on the simplest Cal. 9F61, with the same accuracy and performance, but with a 0.6mm smaller diameter.
Quartz movement (Cal. 9F51). 9 jewels. Stainless steel case (33.0mm diameter, 9.1mm thickness). 10 ATM water resistance. 44 yen each (tax included).
While men have been able to appreciate the sophistication of the 9F quartz movement through larger models, the previous lineup had been difficult for women to wear due to its size. This new model, with a diameter of 33mm, is noteworthy because it offers a compact size for men and a practical, albeit slightly large, fit for women.
It fits well as a compact model for men.
I tried on the Ref. SBGX359 with a white dial; my wrist circumference is approximately 18cm. It paired well with a thick Oxford shirt, a business-appropriate style, and its elegant construction also makes it suitable for dressier broadcloth shirts. It's compact, and its thin 9.1mm thickness allows it to fit comfortably under a sleeve. My wrist size is likely thicker than the average Japanese person, so the compact impression you get from the photos should be taken with a grain of salt.
When worn by a woman, it has a noticeable presence while still being a comfortable fit.
Since we had the opportunity, we also had a woman try it on. The 33mm diameter case is a slightly large size that has a noticeable presence on a woman's wrist. However, the lugs do not protrude and are thinly made, so it fits well and can be said to have a practical silhouette. The case design, which is mainly curved, creates a soft impression, while the sharp indices and hour and minute hands tie the whole thing together.
Furthermore, Mutsuo Ito has shared her impressions of this work from a female perspective, so please check that out as well.
The dial features the classic "snow white pattern."
The dial features the popular "snow white pattern" that has been used since 2005. This pattern represents the natural scenery of the Hotaka mountain range as seen from the "Shinshu Time Craftsman Workshop" within Seiko Epson's Shiojiri Plant, where this watch is manufactured. In winter, the Hotaka mountain range is hit by cold, dry winds that blow across the untouched snowfields, creating wind-blown snow patterns. These wind-blown snow patterns are characterized by random bumps and dips in the direction of the wind. The "snow white pattern" incorporates these wind-blown snow patterns into the dial design. The white dial of Ref. SBGX359 uses a special silver plating process to create a delicate texture without using white paint, and the subtle variations in expression within the pure white are a highlight.
The Ref. SBGX361 with its blue dial features a "snowy white blue" color, reminiscent of the clear sky reflected on snowy surfaces. Inspired by the blue of the sky, its delicate, not-too-intense blue hue is appealing, giving it a unique yet chic impression, making it easy to incorporate into a variety of outfits.
There were still some design aspects that I found concerning.
This watch undoubtedly boasts a universal design that fits a wide range of people, from myself (who has wrists thicker than the average Japanese person) to women. However, I would like to mention a few points that caught my attention from a male perspective. What I found noteworthy was the bracelet's construction. The bracelet paired with this watch has narrow lugs that taper even further. The links are also finely crafted, with ample play and a soft finish. These features undoubtedly contribute to a comfortable fit for both men and women. On the other hand, the tapered design and various other design elements, including the thin buckle, gave me the impression of a delicate design that might be more suited to women.
If any male users are concerned about this point as much as I am, I suggest switching to a leather strap with a smaller tapered design. In my opinion, this will give the watch a more classic and dressy look, revealing a new kind of appeal.
Key compact models you should check out in stores
In the past, when discussing men's dress watches and informal watches, I have stated that "the standard case size in the market is 40mm in diameter." Looking at the lineups of all companies as of 2026, this "standard value" should be correct. However, looking at the new releases from each company, the trend towards smaller diameters is definitely approaching, and the day may come when the standard is rewritten. Looking back at history, 36mm was the standard for a long time, and going further back in time, there were also many models with a diameter of 33mm.
Against this backdrop, the two new Heritage Collection Caliber 9F 33mm models being added to the lineup are finished to the highest standard, allowing you to fully enjoy Grand Seiko's proud 9F quartz movement without compromising on functionality. They are truly exceptional. Not only will male fans seeking compact models and female fans who have been waiting for wearable 9F quartz models be interested, but they are also worth checking out in stores to keep an eye on future trends.
