Original vs. Midsize “Casioak” Watches: Is the GMAS Only For Women? – Casio G-Shock GAMAS2100 vs. GA2100

Posted by Nick L. on June 16, 2021

It’s been over a year since I originally reviewed the Casio G-Shock GA2110SU (also known within watch collecting circles as the “Casioak”). Since then, Casio has continued to release new colorways of the watch including the gray color that I reviewed. I would have thought by now that supply would have caught up with demand, but many of the colors are still often sold out (the watches shown were obtained through diligent searching, and signing up for multiple email waiting lists).

The Casioak is actually so popular, that fakes are being produced now. I have first hand experience with this, as I unwittingly purchased one on eBay recently from an account that had been hacked (I did luckily get my money back). 

Unsurprisingly, Casio has continued to capitalize on the popularity of the series by releasing a new line of slightly smaller Casioaks (denoted by a GMAS2100 reference number versus GA21xx for the larger size). The watches are marketed as being for women, but in my opinion, some (or all) of the colors could also be worn by a man who prefers smaller sized watches. I won’t delve too deep into the debate over watches and gender here, plus Cara Bennett discussed it much more eloquently than I ever could.

Regardless of the stance you take on the matter, it seems that my wife and I fit into Casio’s respective intended audiences. You already know that I love the original Casioak. I recently shared a photo from Instagram of these new “women’s” models, and my wife who does not wear a watch replied to me with how she wanted one! At the time of this writing, Casio makes them in four colors: black, white, peach, and pink. She was drawn to the Peach, and liked black second best. Since Mother’s Day was coming up, I decided to get her one of each and then “borrow” them from her to do a comparison.

My first impression upon receiving them is that people of most wrist sizes could wear either model. At 46.2mm wide, the smaller Casioak is still no dinky timepiece. That being said, G-Shocks always wear much smaller than their numerical size indicates. These watches feel on the wrist the like a conventional watch about 3-4mm smaller. In my experience, the height measurement is a better indication of the way a G-Shock will wear. 45.4 and 42.9mm in the case of these models. There is also a negligible 0.6mm thickness advantage that the GMAS has over the already thin GA.

Color preference is also up to the wearer. I find myself drawn to the more utilitarian colors of the GA models, while my wife prefers the light-hearted colors from the GMAS collections. With the right outfit though, I think that any of the colors could be worn by anyone.

As far as specifications go, the watches are identical. Both boast 200m of water resistance, 3 years of battery life, and are priced roughly the same depending on the version.

The same Casio module is used in either one, so they both have the exact same display and functions. Due to it’s smaller size, the GMAS is also 10 grams lighter than the already featherweight 51 gram GA.

The differences other than size are purely aesthetic. the GMAS models feature a smooth strap, versus the recessed one on the GA. The buckles are also slightly slimmer on the GMAS. The straps are also the same length, but since the GMAS case is 2.5mm shorter, I found myself wearing those models on hole looser on the strap. Finally, the function buttons are color-matched on the GMAS models, versus bare steel on the GA.

Unfortunately, like the GA models, these GMAS variants seem to be selling out quickly. My advice, as before, is search around, as they can be found from various authorized online retailers, many of which allow you to sign up for notifications when they are in stock.

Considering my love for this Casio model, I am excited to see them continuing to expand the line. I’m also happy to have found something to get my wife wearing a watch again (especially something affordable)! Now I just hope to see a more premium version of the Casioak released with solar charging and atomic time keeping…

What do you think of the new GMAS line of Casioaks? Which version do you prefer? Do you think only women can wear one line and only men the other, or can they be interchanged? We’d love to hear your opinions in the comments.

Reference NumbersGA2100-xx/GA2110-xxGMAS2100-xx
Available ColorsBlack, Green, Blue, Gray, Red,Yellow, Clear, Camo, MultiBlack, White, Peach, Pink
Price (USD)$99/$110$99
Width (mm)48.546.2
Height (mm)45.442.9
Thickness (mm)11.811.2
Module Number56105610
Water Resistance (m)200200
Weight (g)5141
Battery Life (years)33


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