In this article, I introduce you to my favorite Casioak: the Casio G-shock GM-2100B-3A. This is an honest review of the watch, after I’ve been wearing it extensively for months. Believe it or not, this is an elegant Casio G-shock that actually looks stunning on the wrist. Not convinced? Give this article a read.
Let me change your mind about Casio G-shock watches!
When you think about Casio G-shock watches, probably the first thing that comes to mind is big, bulky watches that have nothing to do with elegance and style. And for a long time, that was indeed the case. A Casio G-shock was the best watch for tough environments. These watches were designed for endurance and shock-resistance, not for fashion purposes. And that’s why many people today still associate them with toughness and bulkiness, as opposed to fashion or refinement.

If you’re one of these people, like I used to be for a long time, I hope this review will change your mind about Casio G-shock watches. Especially about the Casioak models, which are as elegant as Casio G-shock watches can be. We’re not talking dress watches with tuxedo dials, fancy numerals, or delicate leather straps. But we’re talking about a durable watch that’s good-looking, smart-casual, and that one can wear on just about any occasion, with the exception of formal events.
The Casio G-shock GM-2100B-3A
Let me introduce you to the Casio G-shock GM-2100B-3A, part of the G-steel 2100 Series. With an iconic octogonal bezel resembling AP Royal Oak watch designs by Gerald Genta, this type of Casio G-shock is often referred to as a Casioak watch. You will find a variety of Casioak models on the market today, but this particular variation is the one I personally fell in love with.

From the moment I tried it on, I decided I needed this watch in my collection. This Casio G-shock is not just a highly durable, shock-resistant piece, but it’s also the perfect everyday watch for me – with a casual design that I can wear around the clock, 200-meter water resistance, a multitude of functions, and – most importantly – a stunning green dial that I love looking at whenever I check the time.
Part of the same series there are three other designs available, in different color palettes. Sleek, modern, durable, and not as bulky as expected, right?
Dimensions and materials
If this watch caught your attention, and you’re still here, let me talk about the specs a little bit. The Casio G-shock GM-2100B-3A has a case width of 49.3 mm, a case height of 44.4 mm, and a case thickness of 11.8 mm. What I loved about this Casio G-shock watch is that it’s a great fit for medium wrist sizes, as opposed to the larger, bulkier models. For reference, I have a wrist size of 16.5 cm, and this watch fits me perfectly.



The watch is also lightweight, weighing 72 grams. After wearing it extensively, I can confirm that it does not feel heavy on the wrist.
In terms of materials, we have a resin strap with a quick release function, so it’s easy to take it off or to change it. And, according to the Casio website, a stainless steel bezel with exceptional strength and inner case made of damage- and deformation-resistant glass fibre-reinforced resin safeguards the module inside. Simply put, we have a shock-resistant structure with a metal exterior. Perfect for your everyday adventures.
And since we’re talking adventures, it’s also important to know that this watch has a water resistance of 20 bars, so it’s also fit for swimming and water sports.
Functions
As far as functions go, there’s a whole world of them when it comes to Casio watches. And G-shock watches excel in this area. The Casio GM-2100B-3A boasts a multitude of useful features. To name a few, we have world time, 31 time-zones, stopwatch, countdown timer, 5 alarms, double led light, calendar up to 2099, 12/24 hour format, as well as your basic hour, minute, second, am/pm time, and date display.

I will leave a link here to the product page for this particular Casioak model, so you can read in detail about any of these functions, as they are presented on the Casio website.
What I loved about this watch / PROS
First of all, I was very drawn to the design of this watch. I saw it in a watch store and I had to try it on. And eventually get it, because it looked better than I imagined on the wrist. I was quite put off by G-shock watches before, because of their large sizes and bulky designs. But the 2100 Series is a great alternative for those looking for a smart-casual looking G-shock watch.
Another pro in my book is the fact that this watch perfectly fits medium wrist sizes. So, if you don’t have an extra large wrist, check out the Casioak models. Furthermore, Casio have actually released the mini Casiaoak line, which will fit even smaller wrist sizes. A great alternative to this Casio G-shock watch is the Casio G-shock GM-S2110-3A, in case you want to check it out as well.

Another thing I love about the Casio GM-2100B-3A is the versatility of its design. It was very easy for me to integrate this watch with sporty outfits, like gym attire, as well as with casual and smart outfits. It looks as good with a hoodie, as it does with a denim jacket or with an elegant sweater or shirt. For someone that doesn’t attend formal events on a regular basis, this Casioak model is a great all-round watch. The only watch you need for a smart-casual wardrobe.
One other important pro is how comfortable this timepiece is on the wrist. It’s not too heavy, the strap is well-made, easy to adjust, and even easy to change, if that’s something you’re interested in.
Finally, I also have to mention the obvious pros when it comes to Casio G-shock watches: impressive durability, 200-meter water resistance, and a wide range of functions that you get for a very good price point.
So, to recap: we have – a cool design; great fit for medium wrist sizes; high versatility; comfortable on the wrist; durable; water-resistant; a multitude of useful functions; and a good price point.
CONS
Now it’s time to look at the cons, and for me, personally, there aren’t many. I guess it all comes down to what you expect to get from a watch. As a con, I could mention that fact that this watch is probably not a good choice for extra large wrist sizes. It may look a bit too small.
And another con, but that’s a bit of a stretch, is the fact that you can’t wear this watch with formal attire. So if you’re looking for a one-watch only collection, a watch that works with everything in your wardrobe, the Casioak is probably not it. But can you really have a watch that goes with everything? To wear it to the gym and also to your best-friend’s wedding? Let me know in the comments if you found the one!
Some might complain about the mineral glass crystal of the watch. But there are hardly any brands that offer sapphire crystals at this price point. What I can tell you is that I’ve worn this watch for many months and there isn’t a single scratch on it.
Want to see this review in video form? Check out the video review on our YouTube channel!
The Casio GM-2100B-3A: My favorite model from the Casioak line
All in all, as you can probably tell, I love this watch. From the beautiful emerald-green dial that changes color in the light, to the octagonal dark gray bezel, and to the textured dark green strap, this watch is a conversation starter.

So, that said, let’s start a conversation! What’s your take on the Casioak? Is it better-looking than other G-shock watches? Is it a worthy addition to your collection? Let me know in the comments. And also let me know if you were already familiar with the Casio G-shock GM-2100B-3A from the 2100 Series, featured in this review, or if it’s the first time you come across this variant of the Casioak.
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