Casio Men's G-SHOCK GA-B2100 Series Rubber Band GA-B2100-1A1JFProduct Highlights Introducing the new slim module with optimized circuit board layout to accommodate the increased number of components due to enhanced functionality. By combining it with the carbon core guard structure, we have maintained the compact size of the previous models. The colors of the cases and bands in blue, green, and yellow are inspired by the "First Color" introduced in the 5600 series. The blue, green, and all black models are