This time, I'll be reviewing the Spinnaker "Spence 300 Automatic." This watch, from Spinnaker, a brand that offers watches for people who enjoy marine sports, boasts a high water resistance of 300m and a slim case thickness of 10.9mm, making it a diver's watch that excels in both sports and daily use. I will discuss in detail the practical and well-made quality of this watch from Spinnaker, a brand that I rate as "solid watchmaking."
Photographs and Text by Shin-ichi Sato
[Article published on January 22, 2026]
Spinnikor releases watches for marine sports enthusiasts
The listed thickness refers to the case thickness; the finished watch thickness including the crystal is 11.8mm according to my own measurement. Automatic movement (MIYOTA Cal. 9039). 24 jewels. 28,800 vibrations/hour. Power reserve approximately 42 hours. Stainless steel case (40mm diameter, 10.9mm thickness). 74,800 yen (tax included).
The Spinnaker watch brand, which we'll be reviewing today, is an Italian watch brand that launched in Japan in 2019. The brand's core focus is on designs for people who participate in marine sports such as yachting and freediving.
The main lineup includes vintage-inspired models with a unique twist, such as the "Dumas," which incorporates 1970s aesthetics; the "Blunder," an homage to compressor cases; and the "Picard," a 55 ATM water-resistant model with a bubble lens crystal. Other models include the modern "Has" and the "Tessey," positioned as Spinnaker's high-end series.
The author's impressions of Spinnaker and expectations for the "Spence 300 Automatic"
Spinnaker's lineup includes models like the ridiculously oversized Picard and the "Challenger Automatic Popeye Anchor Arms Limited Edition," a collaboration with Popeye, a sailor-themed comic book, which might lead some to perceive it as a kind of "variety" brand. That is certainly one aspect of Spinnaker. However, its appeal also lies in its excellent sense of balance, skillfully translating unique concepts into watch designs that are both practical and functional. Furthermore, I highly appreciate the clever case shape and bracelet design, the comfortable fit, and the solid construction.
The "Spence 300 Automatic" that I'll be reviewing today is a high-spec, slim diver's watch that boasts 300m water resistance while achieving a case thickness of just 10.9mm. Its key feature is that this thin design prioritizes wearability and practicality. The design is simple, without a date display, and essential.
Based on this preliminary information, I expected that "if the thin construction and simple design were combined with Spinnaker's solid watchmaking, it would be a very appealing timepiece." So, how did the actual finished product turn out? Let's take a closer look.
Key features of the Spence 300 Automatic
The concept behind the Spence 300 Automatic is to achieve both high water resistance of 300m and a comfortable fit thanks to its slim 10.9mm thick case (the finished watch thickness is 11.8mm according to the author's measurements). Therefore, paying attention to the wearability is crucial in evaluating the quality and capabilities of this timepiece.
The overall styling draws inspiration from conservative diver's watches, but the dial design adds originality with a large, arrow-shaped hour hand and a minute hand that tapers sharply towards the tip.
The case shape is based on curves, giving it a soft impression. The entire watch features a fine satin finish, while the edges are polished, creating a modern look. The model I reviewed has a blue dial with a subdued brightness but high saturation, and the color changes from bright blue to deep navy depending on the light, giving it a modern feel. An aluminum bezel insert is added to this, giving it a retro touch.
I am very satisfied with the excellent fit.
When I picked up this garment, even though I knew beforehand that it had a slim fit, my first impression was that it was "slimmer than I expected." When I tried it on, I noticed that it fit well and had excellent weight balance.
In addition to its slim design, the case back protrudes minimally and is nearly flat, and there is almost no lifting of the lugs. The minimal lug lift also contributes to the wide range of motion of the bracelet. Furthermore, the buckle features a length adjustment mechanism that allows for changing the attachment position of the spring bars, with five adjustment steps of approximately 2.5 mm each (maximum of approximately 1.2 cm), making it easy to adjust even for a tight fit, which is a highly appreciated feature.
Furthermore, the thin case means the head is also lighter, and the weight balance is maintained even with the thin bracelet of this model. As a result, the overall weight is light, and with the bracelet adjusted, my measurement was 142g. Moreover, being thinner means the heavier components are closer to the wrist, and the moment of inertia is also reduced. This leads to a reduction in the actual perceived weight when wearing it and moving your arm.
In summary, the wearing comfort of this product is excellent, and I am very satisfied with it.
A movement with excellent visibility and high practicality.
This watch features a large, arrow-shaped hour hand and a minute hand that tapers towards the tip, creating a clear and easy-to-read design. The use of different index shapes—triangles, dots, and bars—depending on the position makes it easy to determine the watch's orientation. The dot at the 0-minute mark and the indices placed every 5 minutes on the bezel are coated with yellow luminous paint, enhancing visibility in the dark. Therefore, this watch can be considered to have excellent legibility.
The movement is a Miyota Cal.9039. It boasts a sufficient power reserve of approximately 42 hours and employs a unidirectional winding mechanism, which is considered advantageous for desk work. While rigorous testing wasn't possible, it possessed sufficient practicality without any noticeable shortcomings.
Variations available
The Spence 300 Automatic is available in three variations, including this one. The model reviewed here features a blue sunray dial with a navy bezel insert and yellow luminous paint. The other variations include a green dial and bezel insert with yellow luminous paint, and a black dial and bezel insert with white luminous paint. The black model features red markings for "1000ft/300m" and a red dot on the tip of the second hand, giving it a classic diver's watch feel.
Automatic movement (MIYOTA Cal. 9039). 24 jewels. 28,800 vibrations/hour. Power reserve approximately 42 hours. Stainless steel case (40mm diameter, 10.9mm thickness). 74,800 yen each (tax included).
All models are priced at 74,800 yen (including tax). Considering this price, the concept of "combining high water resistance with excellent wearability" is achieved, the overall weight balance is excellent, and the case finish and legibility are highly commendable. The case and bracelet end links have a sense of unity, which also contributes to its appearance. All in all, this model is highly accomplished and can be evaluated as a timepiece that allows you to experience Spinnaker's solid watchmaking.
The Spence 300 Automatic is a car that is so well-made that it makes you genuinely think, "I want one!"
Finally, let me offer my own very personal opinion. The Spence 300 Automatic is compact, comfortable to wear, and high-spec—it perfectly matches my preferences. For that reason, I had a lot to say in this review, and I finished writing it quite quickly.
So, what did I do during the second half of the rental period? I would open online shops and look at them alternately with the Spence 300 Automatic I had on hand, wondering things like, "It's reasonably priced, maybe I should buy it," or "If I do buy it, which color would be best?" If it aligns with my preferences, I can confidently say you'll love this model. I encourage you to pick it up in a store, try it on, and take your time deciding.
