Casio Men's G-SHOCK Metal Covered Model GBM-2100A-1A2JFProduct Highlights Since its launch in 1983, the G SHOCK tough watch has been evolving relentlessly in pursuit of unwavering strength. Introducing the GBM 2100 model, a metal covered model equipped with smartphone link and Tough Solar while maintaining the slim size characteristic of the 2100 series. The octagonal form of the 2100 series remains intact, but with the addition of smartphone link and Tough Solar in a metal bezel, the GBM 2100 comes in