Since its introduction in 2019, the slim profile and Genta-esque octagonal case design of the Casio G-Shock GA2100 series have made the “Casioak” both an instant classic and an enthusiast fixture in the Japanese giant’s durable and multifaceted watch lineup. For its latest release, Casio looks to add a more premium feel to this smash hit entry-level design, bringing a stainless steel-clad flash to the brand’s signature shock resistant resin case concept. The new Casio G-Shock GM2100 series elevates the successful “Casioak” formula with more nuanced finishing, but maintains the durability, functionality, and affordability that help to define the long-running G-Shock sub-brand.



Measuring in slightly smaller than the original resin GA2100 design at 44.4mm across (the GA2100 features a diameter of 45.4mm), the stainless steel and resin case of the Casio G-Shock GM2100 series offers a surprisingly svelte profile by G-Shock standards. While the broad octagonal bezel, ridged case sides, and integrated hooded lugs are carried over from the full resin version, Casio gives the GM2100 design greater nuance with a combination of materials and finishing. For the GM2100-1A, the brand keeps the stainless steel outer case brightly polished, with the exception of coarse radial brushing atop the octagonal bezel and along the case sides. Each of the three other variants in the line add an aggressive layer of dark ion plating to this finishing formula, bringing the designs more in line with the classic black resin G-Shock aesthetic in images. With the GM2100B-3A and GM2100B-4A the brand opts for a charcoal gray coating, offering a touch of contrast with the darker strap design. For the GM2100N-2A, Casio instead uses a deep desaturated midnight blue ion plating, creating a multi-tonal blue-on-blue colorway with the dial and strap. All four models use inner cases in classic G-Shock resin with stainless steel casebacks, and like all G-Shock designs the GM2100 series offers a robust 200 meters of water resistance and immense shock protection.




Like the cases, the dials of the Casio G-Shock GM2100 series give depth to the clean ana-digi design of the GA2100 with metallic texturing and new materials. The bare stainless steel GM2100-1A accents its bright case finishing with a steel gray main dial surface, giving the familiar look a more luxe texture in images with dramatic vertical brushing. The inverted digital subdial stretching between 3 o’clock and 6 o’clock is carried over more or less verbatim from resin-cased variants, as are the broad tapering sword hands and the layered retrograde pointer date display at 9 o’clock. The other three models in the GM2100 series take this simple formula in wilder visual directions with the use of color. By far the most aggressive of the group is the GM2100B-4A, which renders every element of the dial in a bold ruby red tone. Even the digital subdial uses a red background, and although this look is dramatic and stylish there is a marked impact on legibility in images. The GM2100B-3A appears to strike a more usable visual balance, pairing a grassy green brushed dial surface with functional elements in high-contrast black. Lastly, the GM2100N-2A uses widely varying textures and shades of blue to create an attractive and solidly functional monochrome aesthetic.


All four models in the Casio G-Shock GM2100 series use the brand’s in-house Module 5611 ana-digi quartz movement. Like most G-Shock movements the Module 5611 packs in a robust suite of complications, including a 1/100 second chronograph, a 24 hour countdown timer, a world timer, a perpetual calendar, five daily alarms, dual LED dial illumination, and radio controlled time correction with an hourly time signal. Base accuracy for the movement stands at +15/-15 seconds per month, with a claimed battery life of three years. Casio pairs each model in the series with an accordion-style integrated resin strap featuring a raised waffle pattern texture. Both the GM2100-1A and the GM2100B-4A interpret this strap in classic G-Shock black, while the GM2100B-3A and GM2100N-2A add subtle color with extremely dark forest green and navy blue, respectively.


With more premium materials, more complex finishes, and more nuanced use of color, the Casio G-Shock GM2100 series successfully refines the fan-favorite “Casioak” concept without losing sight of the durable and affordable core tenets of the design. All four models of the Casio G-Shock GM2100 series are available now through select G-Shock retailers and the G-Shock Soho Store. MSRP for the Casio G-Shock GM2100 series starts at $200. For more details, please visit the brand’s website.