We present our impressions of the new "Speedtimer Mechanical Model," a three-hand model newly added to the Seiko Prospex "Speedtimer" series. This model is based on the concept of "accurate time measurement" that is a feature of conventional chronograph models, and although it has three hands, the inner bezel allows measurement down to the minute. The design combines the taste of tool watches and sports watches with the chicness of informal watches, making it easy to incorporate into a variety of outfits and making it an appealing choice.
Automatic movement (Cal. 6R55). 24 jewels. 21,600 vph. Power reserve approximately 72 hours. Stainless steel case (diameter 39.5 mm, thickness 12.0 mm). Water resistant to 20 bar. Price: 46,200 yen (tax included).
Text and Photographs by Shin-ichi Sato
[Article published on January 18, 2025]
"Speedtimer" inherits the name of the legendary chronograph model
This time, I'll be reviewing the Seiko Prospex "Speedtimer Mechanical Model" Ref. SBDC215, which was announced in July 2025. It's a three-hand model with an inner bezel, and its design combines the feel of a tool watch or sports watch with the chicness of an informal watch. Before I begin my review, let's take a look back at the "Speedtimer."
The Speedtimer name dates back to the 1969 Speedtimer, the world's first mass-produced mechanical automatic chronograph. The 1969 Speedtimer featured a vertical clutch and column wheel, which reduced hand misalignment and jumping during start and stop movements while also achieving stable operation, greatly influencing subsequent chronograph development. The Speedtimer was then put on hold, but was revived in 2021 as part of the Seiko Prospex series. Today, it is gaining popularity as a collection that offers a unique experience of Seiko's sporty styling and chronograph technology.
Impressions of the three-hand Speedtimer Mechanical Model
The Ref. SBDC215 we'll be reviewing is notable for its three-hand styling, incorporating details from the 1969 Speedtimer and subsequent chronograph models. While the "Seiko Presage Style 60's," which incorporates the design of the classic Crown Chronograph, exists as a three-hand model inspired by chronographs, as of December 2025, there are only two regular three-hand models bearing the Speedtimer name: this model and the same design with a black dial.
Some people may have the first impression of this watch as, "It's not a chronograph, so why is it called a Speed Timer?" Those people should read this review and learn about the lineage, appeal, and high level of perfection of the Speed Timer as I feel it.
An example of the use of the inner bezel, a distinctive feature of this watch
What symbolizes the name of this model as a Speed Timer is the inner bezel, which is operated by the crown at 4 o'clock. This type of inner bezel was also used in the 1969 Speed Timer, and like the rotating bezel, it allows you to set an arbitrary reference position to measure time.
While the 1969 Speed Timer was a count-up watch, the inner bezel used in this model is a count-down watch. Starting from a reference triangle, the time counts down clockwise to "55," "50," then "10," "05," and finally to zero. Here's an example: If your Shinkansen train is due to arrive at your destination at 10:30, set the triangle to the 6 o'clock position. Then, if it's currently 10:6, you can see from the inner bezel that there are 24 minutes remaining. Or, if you decide to concentrate on practicing guitar for 30 minutes, you can simply align the "30" position on the inner bezel with the current minute hand position, and the minute hand will then measure the remaining time.
The design, with its precise scale, evokes the lineage of chronograph models
The inner bezel is easy to operate and doesn't feel catchy or stiff. However, when wearing the watch, the crown at 4 o'clock may come into contact with the back of the hand, causing the inner bezel to move slightly. It's not noticeable, but it's worth noting.
The inner bezel and dial are well integrated, and the design does not "float." The various scales are also clear and highly visible. The seconds scale on the dial is particularly precise and easy to read, giving a sense of the lineage of chronograph technology and the know-how that Seiko has accumulated over the years. From a distance, it appears simple, but the details are packed with information, and the tool watch feel is what makes this watch so appealing.
In this model, the tip of the second hand and the triangle mark from "15" to the zero on the inner bezel are orange, which serves as a design accent and improves visibility. The orange color is exquisite, adding a classic impression to the overall look, as if the red has been burned and faded.
A dial with a good balance of visibility and design
The hour and minute hands are designed to taper slightly toward the tip, with a thin line at the tip to aid in accurate timekeeping. They are also coated with luminous paint to ensure visibility in the dark. The minute hand extends all the way to the inner bezel for a bold look, and the hour hand is positioned opposite the index, which is also nice. The gray bar indexes have an edgy, modern finish. The indexes are surrounded by square luminous paint, likely a homage to the 1969 Speedtimer.
The dial features vertical stripes and a lustrous silver-white color. The finish and color create a chic, classic feel. It coordinates well with the orange of the inner bezel and second hand. The Ref. SBDC217, which was also announced at the same time, has a black dial that looks almost charcoal gray, and is also chic and classic, making it an attractive choice.
Highly rated for its comfortable fit and ease of use with a wide range of styles
The case diameter is 39.5mm, and the finished thickness of the watch is 12.0mm. Wearing it on myself, whose wrist circumference is approximately 18cm, I found the sharp case design, lug shape that fits the wrist, and bracelet that conforms to the wrist to be comfortable and feel more compact than the numbers suggest. The perceived compactness evokes the styling of a dress watch, perhaps helping to add a touch of chic and elegance to this watch. This time, I tried pairing it with an Oxford shirt for a business setting. It also pairs perfectly with outdoor wear.
The bracelet is relatively thin, with short links connected by two small links. This reduces the overall weight of the watch, while increasing the bracelet's range of motion and improving the fit. The weight balance is also good.
A high level of perfection with no demerit points to be found
This watch is equipped with the Cal. 6R55 automatic movement. The Cal. 6R55 boasts a power reserve of approximately 72 hours, allowing it to continue running even if not worn over the weekend, as long as it's properly wound. It's also a 6R-series movement that has been manufactured for many years and is also used in diver's watches, giving it a sense of security. It's water resistant to 20 bar, meaning it can't be used for diving, but it's perfectly suitable for everyday use.
As mentioned above, the watch has good visibility and comfort, is sporty yet chic, and can be easily incorporated into a variety of styles. It also features details that reflect its concept and worldview. The case, bracelet, and dial are well-finished, making it satisfying to wear. The only thing that bothers me is that the bracelet clasp only has an adjustment range of about 5mm, but this is a matter of personal preference. There are no flaws in terms of appearance or performance.
Looking at the whole game, you can see that there are no demerit points. In other words, it is highly polished. The rest is left to whether you like the concept and design.
A Speed Timer mechanical model that clearly reflects the Speed Timer lineage
If you are looking for a "chronograph" in a Speedtimer, you may be dissatisfied or find this model lacking. But wait a moment. Perhaps Seiko has expanded the definition of the Speedtimer to include a collection that "measures time accurately."
As evidence of this, this watch features an inner bezel that supports accurate timekeeping down to the minute, a precise scale, and various details that enhance visibility. As someone who owns a 1969 Speed Timer, when I tried wearing this watch, the way I used the inner bezel really connected to the feeling of "using a Speed Timer."
Even though I'm pressed for time, I often find myself wasting my time by mindlessly watching social media or streaming videos. For me, wearing a speed timer has given me the opportunity to measure time accurately. It was also meaningful to be reminded of the importance of "valuing time" through timing.
