The MTG-B4000B, released in June 2025, retains the MT-G series' concept of "combining different materials," but is the first commercially available Casio watch to incorporate AI into its development process. While retaining the industrial feel of the MT-G, the model's proportions are sleeker than previous models. It's a timepiece that exudes a truly Casio-esque, adventurous attitude.
Photographs & Text by Yuzo Takeishi
[Article published on January 16, 2025]
AI-based development process that started with a concept model
The first MT-G model, the GC-2000, was released in 1999. The concept of "combining metal and resin" that was introduced at that time has continued to this day, and the current MT-G lineup maintains the massive proportions that are characteristic of G-SHOCK, while incorporating metal materials to create a luxurious look.
The MTG-B4000B, released in June 2025, is also a model that follows this concept. The exterior is made of stainless steel and carbon fiber reinforced resin, but what sets it apart from previous MT-G models is that it was developed using AI, a first for a Casio watch on the market.
Tough Solar. Operates for approximately 18 months on a full charge (power save mode). Stainless steel and carbon fiber reinforced resin case (56.6mm x 45.3mm, 14.4mm thick). Water resistant to 20 bar. Price: 176,000 yen (tax included).
The first model Casio created using AI was the G-D001, announced in 2023. This was the second in the Dream Project, following on from the DW-5000 IBE SPECIAL, G-SHOCK's first concept model. This model also used 18K yellow gold for the exterior, but what really caught my eye was the organic design, with its complex interweaving of multiple frames. How would AI be incorporated into Casio's commercial models in the future? This was the question that sparked my interest and expectations at the time.
The G-D001 is the second part of the Dream Project, produced to commemorate the 40th anniversary of the birth of G-SHOCK. The AI development process used for this model was also incorporated into the MTG-B4000.
A cutting-edge design that is characteristic of MT-G, realized through collaboration with AI
It's been about a year and a half since the G-D001 was announced. This commercial model, developed using AI, was released in the MT-G series, which (to me) seems a bit unexpected. Perhaps as a reaction to the G-D001's overly eccentric design, my first impression of the MTG-B4000B was that it was "sleek, despite being an MT-G." This is no surprise, as the collaboration between AI and the development team resulted in a new shock-resistant structure and styling. The case is surrounded by a laminated carbon frame, supported by metal parts at 12 and 6 o'clock. This new structure eliminates the need for screws to connect the case to the strap, resulting in a sleeker look.
This results in the striped pattern unique to the carbon laminate frame appearing on the side of the case, but the fact that this design is not overemphasized but remains a moderate accent is also a good impression. However, my personal favorite is the view from the 6 o'clock side. The design of the carbon laminate frame combined with the stainless steel bezel is reminiscent of modern buildings and futuristic vehicles, giving the impression that G-SHOCK design has entered a new realm.
This is likely due in large part to the coloring and finish of the bezel and other metal parts. The MTG-B4000B in particular has a calming blue-gray color achieved through IP processing, yet exudes a unique presence. What's more, the metal parts are meticulously finished with different finishes, using hairlines and polishes on each surface. When light hits the watch, the way some of the metal parts sparkle between the carbon laminate frame is also very satisfying.
As expected from G-SHOCK, the practicality is undeniable
The case size of this watch is 45.3mm. It is quite large compared to a typical mechanical watch, but it is quite comfortable to wear. Full titanium and full carbon watches are certainly light, but I personally find it strange that "you can feel the watch on your wrist but it doesn't feel heavy." However, this watch combines stainless steel and carbon fiber resin, giving it a moderate lightness and weight, and therefore the weight of the head does not cause the watch to tilt. While it depends on the wearer's preference, this weight balance is something to be highly praised.
The high level of readability is also impressive, as you'd expect from a G-SHOCK! As usual, the dial has many components, including a second time zone display at 3 o'clock, an AM/PM indicator for the second time zone and the day of the week indicator at 4-5 o'clock, a function indicator at 7-8 o'clock, and a 24-hour indicator at 10 o'clock, making it quite a crowded display. However, the main indexes and hour and minute hands are clearly highlighted, allowing the current time to be read instantly. The subdial displaying the second time zone is also small, but the contrast between the dial and the hour and minute hands ensures that it is also highly legible.
I'd also like to mention the compatibility with the smartphone application "CASIO WATCHES." By connecting to a smartphone via Bluetooth, you can not only set the correct time, but also check the remaining battery life of the watch. However, the most useful feature of this application is that you can check how to set the various functions of the watch. The G-SHOCK is particularly multifunctional, making it very useful when you're out and about (especially when traveling abroad). I use this application with my personal G-SHOCK, so I didn't discover anything particularly new, but I want to emphasize once again that it's very practical.
Expectations are rising for G-SHOCK x AI
It was a surprise that the MT-G was the first commercially available product to incorporate the AI development process. At the time of its release, I was quite impressed by Casio's development capabilities, which allowed them to achieve a design that was more in line with mass production, rather than the eccentric design seen in the G-D001. It not only provides a comfortable fit, but also maintains the basic G-SHOCK performance of shock resistance, making it just as practical as previous G-SHOCK models.
As early as November 2025, the company will release the GMW-BZ5000, which incorporates an AI-assisted development process, evolving a model based on the first G-SHOCK. Going forward, how will the collaboration between AI and the development team evolve the standard model, and how cutting-edge will it be? Holding the MTG-B4000B in your hands makes you even more excited for the future of G-SHOCK.
