G-Shock Watch Tough Solar 2100 Bluetooth GA-B2100-1AER. With Bluetooth connectivity and a solar charging system, the new GA-B2100 shock-resistant watches take the iconic 2100 series to a whole other level. The Tough Solar charging system effectively converts light from any light source to power the watch, eliminating the need to replace the battery, and Smartphone pairing via Bluetooth delivers accurate timekeeping. Combining the Carbon Core Guard structure, which protects the module and provides both shock resistance and a compact case, with G-SHOCK classic colours first used in the G-SHOCK 5600 models enables you to wear the latest, and the greatest G-SHOCK has to offer. GA-B2100-1AER has classic black styling with a white LCD.