The Casio G-Shock GA2100-1A1 Black, released in 2020, may be the most successful of any new model in quite some time. Immediately sold out everywhere it was available, the GA2100-1A1 was an instant classic. Featuring G-Shock's new carbon core, the body of the GA2100-1A1 is a high-strength resin that is reinforced with carbon fibers. Add the slim profile, blacked-out features and gorgeous analog-digital display it's easy to see why the GA2100-1A1 is a winner.