CASIO G-Shock GA-B2100-2AJF men's navy-blue Bluetooth-equipped Tough Solar watch featuring an octagonal matte resin case and matching strap, analog-digital grey dial with luminous hands and rugged "PROTECTION" bezel. G-SHOCK GA-2100 Watch The octagonal shape of the GA-2100, inheriting the design concept of the first G-SHOCK, now includes smartphone link and tough solar features. A new thin module with optimized board layout was developed to accommodate an increase in parts due to enhanced functionality. Combined with the carbon core guard structure, it maintains the size of previous models. The case and band colors in blue, green, and yellow are a nod to the "First Color" introduced in the 5600 series. The blue, green, and all-black models have minimal color schemes. Shock-resistant Tough solar (solar charging system) 20-bar water resistance Mobile link function (Bluetooth connection with compatible smartphones) Needle evacuation function World time for 38 cities Stopwatch, timer, alarms, and more For full product features and requirements such as smartphone compatibility, visit the CASIO website.