The G-SHOCK GA-2100 Utility Black Series is a new twist on the original iconic stealth model GA-2100-1A1 model, born by adding fluorescent highlights. These watches retain the simplified bezel lettering and black dial of the original, and the GA-2100-1A3ER has neon green details on the hands, hour marker tips, day indicator, and dial labels. The lightweight GA-2100 is still the slimmest G-SHOCK men’s model, and features a a Carbon Core Guard structure with an interior case made of carbon fiber-reinforced resin.