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We’ve said before at ABTW that one of the greatest strengths of the Casio G-Shock is its breadth of designs. The brand offers watches in a wide variety of prices, sizes, and styles. Models in its G-Steel line sit in the middle of the brand’s price range, bridging the gap between the flagship models that can reach four figures and the entry-level resin case models. Models in the G-Steel range, of course, feature metal cases, but still provide the extreme toughness that G-Shock buyers expect. They also offer some of the brand’s more advanced features.
Because of everything that is packed in, the G-Steel models tend to be thick watches, but this GSTB400-1A breaks that mold. The use of G-Shock’s carbon core guard structure allows the brand to make thinner watches that still meet its shock requirements. Despite having a built-in solar panel, the module thickness has also been reduced (module 5657 in this case). These updates make this the thinnest G-Steel model yet at 12.9 mm. The brand says it is over a millimeter thinner than the GSTB100 models that it sits next to in the catalog.
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Despite its thinner size, the GSTB400 is still water-resistant to 200m. It also includes familiar high-end G-Shock features like tough solar, a super-illuminator double-LED light, and a hand retract function that makes it easier to view the sub-displays. Bluetooth smartphone connectivity adds functionality, such as automatic time adjustment and a phone finder feature. The G-Shock connected app also makes it much easier to make adjustments to the watch. Owners of conventional G-Shocks will appreciate this, as it can be difficult to remember the steps required to make adjustments via the pushers alone. The watch is still, however, designed to work autonomously from your phone if you prefer not to connect it.
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The GSTB400 range is available in a variety of colors and finishes, including a model with a carbon fiber bezel, and some with silver or black-coated stainless steel bracelets. This “-1A” variant of the line is the standard and most legible model. It features a non-coated stainless steel case, a black resin strap, and a black dial with white hands.
The multi-piece case is a sandwich of multiple steel pieces surrounding carbon. An intricate bezel is affixed to the main case with visible screws. G-Shock says it has been given five different finishes, including a brushed top surface and polished flanks, and the wording on the bezel is recessed and filled with black paint. In addition to looking good, this indicates the pusher functions, making the watch more user-friendly. The other thing that makes the pushers easier to use is their large size. Some G-Shock models tend to have smaller buttons that are more difficult to engage. The ones on the GSTB400 are easy to press even for people with large fingers, or while wearing gloves. Deep cutouts in the case still protect them from being accidentally pressed or contacting your wrist.
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“Ana-digi” G-Shocks always provide a good compromise between legibility and functionality, and the GSTB400 is no exception. Despite the slightly busy dial, the time can be read at a quick glance thanks to large white sword-shaped hands and large rectangular hour markers (all of which are filled with Casio’s Neobrite luminous paint). These hour markers extend into the dial via large, textured metal indices. Grooves on their top surfaces reflect light at certain angles, which further aids legibility.
Metal surfaces on the dial have a variety of textures and are coated in dark gray multi-layer vapor deposition. This allows them to blend into the dial better and gives a more mature look. Minutes are read via bright red hash marks on the chapter ring, and two small digital windows allow more information to be displayed compared to a fully-analog G-shock. This includes the date, running seconds, and the other various timing, alarm, and world-time functions. On the left side of the dial, there is also a blade-like rotating multi-function display. It indicates which function the wearer is currently using and can also indicate how much of the seven-month power reserve remains (up to 18 months if the watch enters power save mode).
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Recently, some of the metal G-Shock watches have been equipped with more intricate strap designs, and the GSTB400-1A follows suit. Rather than a mostly smooth strap that owners of older G-Shock models might expect, this watch features a unique pattern of interlaced pyramids. This gives the watch the feel of a more premium product. This is welcome, as the resin strap models often feel like a lower-cost product than the stainless steel bracelet models. Additionally, all of the straps and bracelets in the GSTB400 range feature quick-release spring bars. This makes them easy to swap without having to remove screws if a buyer were to purchase a metal bracelet or different color strap from one of the other variants.
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Overall, the “Goldilocks” approach that Casio has taken with the GSTB400 series works well. The watch features a number of notable upgrades from the entry-level models, but the price is still affordable. Buyers get a variety of useful tech features and construction techniques from some of the brand’s more expensive watches, such as Bluetooth connectivity and multi-piece steel and carbon core construction. The 12.9mm thickness and the well-finished metal case and bezel also make it more versatile than some of the thicker and more brightly-colored models. Owners might feel comfortable wearing this watch in a wider variety of situations than some of the brand’s other models, and they are getting the experience of a premium G-shock product without breaking the bank. Price for the Casio G-Shock GSTB400-1A watch is $320 USD. Learn more at the Casio G-Shock website here.