Casio G-SHOCK GA-B2100 Series Men's Rubber Band Watch GA-B2100C-9AJFProduct Highlights Introducing a new slim module with optimized circuit board layout to accommodate the increased number of components due to enhanced functionality. By combining it with a carbon core guard structure, we have maintained the compact size of the previous model. 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 finished