Casio G-Shock [GRX5600SRF-3] Sports Watch The strong solar power system of Casio G-Shock GRX5600SRF-3 is persistently harnessing the power of the sun, which is an escort for surfers worldwide. By converting sunlight and even non-natural light into energy, this system generates sufficient power for the watch functions such as 5 alarms (to make sure you [...]