The Casio GA-B2100-1AER smartwatch features a shock-resistant design with a round plastic case and a black resin strap secured by a traditional buckle. It boasts a black dial protected by mineral crystal glass and is powered by a reliable quartz movement. This model offers water resistance up to 200 meters, ensuring durability in various conditions. Key functions include an alarm, hourly time signal, automatic calendar, battery level indicator, Bluetooth connectivity for smartphone pairing, a countdown timer, date and weekday display, and an auto-illuminating LED light for low-light visibility. It also features a hand shift function for unobstructed screen viewing, multi-language display options, Neobrite luminous hands, shock-resistant construction, and a solar power system that converts light into energy, eliminating the need for battery replacement. The watch includes a stopwatch and world time functionality, displaying the current time in major cities globally. Enhanced by Bluetooth connectivity and a solar charging system, this model elevates the iconic 2100 series. The Tough Solar system efficiently converts any light source into power, negating the need for battery changes, while smartphone pairing via Bluetooth ensures precise timekeeping. Its Carbon Core Guard structure protects the module, providing shock resistance and a compact case. The classic G-SHOCK black and white color scheme offers a stylish aesthetic. Additional features comprise 5 daily alarms, auto calendar, countdown timer, hand shift function, display illumination, stopwatch, and world time. With a 49mm case and 200m water resistance, it represents the pinnacle of G-SHOCK technology.