Colloquially known as the “Casioak” among collectors due to its octagon-shaped case profile, the Casio G-Shock 2100 series has been a runaway success for the Japanese manufacturer since it first debuted in 2019. In the years since its launch, the Casioak lineup has exponentially expanded, and in addition to creating countless different iterations of the original full-size model, Casio has also introduced smaller versions of the G-Shock 2100 series that open up this fan-favorite model to a wider range of wrist sizes. Among the brand’s more recent releases for 2024 is the Casio G-Shock GMAP2100SG Sunset Glow collection, which iterates upon the blueprint of the smallest Casioak with a trio of models that feature colorways inspired by summer sunsets over the water.

Based upon the G-Shock GMAP2100 series, the Casio G-Shock GMAP2100SG Sunset Glow models are noticeably smaller than their full-size counterparts, and all of their dimensions have been reduced to create one of the smallest G-Shock watches currently available. While the standard full-size Casioak measures 45.4mm in diameter by 11.8mm thick with a lug-to-lug distance of 48.5mm, the G-Shock GMAP2100SG Sunset Glow series is noticeably smaller at 40.2mm in diameter by 11.2mm thick, with an overall lug-to-lug profile of 46mm. Additionally, the weight of the GMAP2100 series is nearly 20% lighter than their full-size siblings, with a total weight of 41 grams, including their straps and buckles.

Just like many G-Shock models, the on-paper dimensions of the GMAP2100 series are slightly misleading, and the watches wear noticeably smaller than their official diameters might otherwise suggest. In the same way that the standard full-size Casioak feels significantly more compact than its on-paper 45.4mm case measurement, the G-Shock GMAP2100 models also feel quite a bit smaller than their 40.2mm diameters, and they ultimately wear closer to something with a case size in the 36mm to 38mm range. While I typically associate G-Shock watches with a rather chunky and oversized appearance, the GMAP2100 series represents a significant reduction in size, and its ultra-compact proportions promote an incredibly easy-wearing experience on the wrist.

While the fundamental case architecture of the Casio G-Shock GMAP2100 series is largely identical to the standard Casioak GA2100 series and even the midsize GMAS2100 models, they do not feature the same Carbon Core Guard structure, and their cases are instead crafted from resin and then fitted with the usual soft resin bezel and screw-on stainless steel caseback. The rest of the G-Shock GMAP2100 watches follow in the footsteps of their larger siblings, and they are fitted with flat mineral glass crystals above their dials and four buttons located along the sides of the case; water resistance comes in at the same 200 meters that is standard across the greater G-Shock collection.

At the time of writing, the Casio G-Shock GMAP2100SG Sunset Glow series spans three different colorways, which include the pink GMAP2100SG4A, purple GMAP2100SG2A, and black/gold GMAP2100SG1A. While the pink and purple models both embrace pastel hues for a softer and slightly more feminine appearance, the GMAP2100SG1A featured here represents the most gender-neutral offering, with its largely black exterior and metallic gold dial. Aside from their colorways, the three G-Shock GMAP2100SG Sunset Glow models are otherwise identical, and all of them feature resin cases that are covered by bezels made from the same bio-based resin that is steadily making its way throughout Casio’s catalog.

To accommodate their significantly smaller format, the Casio G-Shock GMAP2100 models omit the sub-dial at the 9 o’clock location that can be found on their larger counterparts. With that in mind, they still feature two centrally mounted hands for displaying the time, along with the same rhombus-shaped digital screen on the lower right-hand side of their displays. Additionally, to further lean into the theme of the collection, the three G-Shock GMAP2100SG Sunset Glow models are fitted with metallic dials, which are created using a vapor position process and showcase a vertical gradient effect that is intended to be reminiscent of the setting sun when viewed from across the water.

Powering the Casio G-Shock GMAP2100SG Sunset Glow watches is Module No. 5730, which is the same analog/digital hybrid quartz movement that can also be found inside other models from the greater GMAP2100 collection. Running on a single CR1025 power cell with a battery life of approximately three years, Casio’s Module No. 5730 offers all of the same features that you will find among the larger entry-level Casioak watches, and while it doesn’t include an analog day-display register at the 9 o’clock location, it still features all of the usual digital sports watch functions, such as a stopwatch, alarm, countdown timer, perpetual calendar, world timer, and LED backlight.

Despite having a significantly reduced case profile, the Casio G-Shock GMAP2100 series still features the same 16mm lugs that you will find on most full-size G-Shock models, and attached to them is a two-piece strap that is made from the same black bio-based resin that is used for the bezel. Immediately flaring out to 23mm to create an integrated appearance with the case before tapering down to 18mm where it connects to a stainless steel buckle, the strap fitted to the G-Shock GMAP2100 models offers the same overall design as what you will find on the larger Casioak watches, although its dimensions have been reduced in every way possible. In addition to being narrower than the straps fitted to the full-size models, the strap for the GMAP2100 series is also shorter to help it better accommodate smaller wrists.

While the Casio G-Shock GMAP2100 series is first and foremost intended to cater to individuals with slender wrists, its highly compact case proportions also make it a viable alternative for those who want a G-Shock without the oversized profile that is typically characteristic of the brand’s models. Although the Casio Baby-G series has offered a wide variety of compact cases since 1994, it has always been less performance-oriented than the G-Shock lineup, and this is illustrated by the fact that Baby-G models offer half the water resistance of their G-Shock counterparts. While I openly admit that I am hardly the most manly guy out there, I still can’t bring myself to wear a watch with the words “BABY-G” boldly emblazoned upon its bezel, and this has always been a sticking point for me when it comes to Baby-G watches.

As someone who has smaller wrists (approximately 6.5 to 6.75 inches), I personally very much enjoy the concept of a reduced-size G-Shock, and while the G-Shock GMAP2100 series succeeds at creating a smaller version of the ultra-popular Casioak, the colorways available for the G-Shock GMAP2100SG Sunset Glow collection undeniably feel like they are primarily intended to appeal to a female demographic. Watches are inherently rather unisex items, although light pink and pale purple are stereotypically feminine colors, and the black and gold GMAP2100SG1A featured here is the only model from the G-Shock GMAP2100SG Sunset Glow collection that I can see being widely adopted by male collectors. 

The widespread popularity of the Casioak has been nothing short of astonishing, and Casio has produced this fan-favorite model in virtually every colorway imaginable. With that in mind, the size of a watch can often be a deal-breaker for buyers, and a smaller-sized version of the 2100 series is the single most effective way to expand its relevance to a wider audience. Due to their metallic gradient dials, the Casio G-Shock GMAP2100SG Sunset Glow watches are slightly more expensive than the standard GMAP2100 models, and all three colorways are priced at $120 USD. Given that they cost roughly the same as a decent pair of sneakers and offer the legendary durability that has made the G-Shock collection famous, the GMAP2100SG Sunset Glow models are the definition of budget-friendly horological novelties, and they are perfectly positioned to be fun and carefree summer timekeeping companions. For more information on the Casio G-Shock GMAP2100SG Sunset Glow collection, please visit the brand’s website.