Casio G-Shock GGB100X-1A3 MUDMASTER Quad Sensor Bluetooth Mens Green WatchThe MUDMASTER GGB100X employs high rigidity carbon for the carbon fiber reinforced case to keep damage and warping at bay and ensure a tight seal and excellent shock resistance. Featuring a filter to protect against mud, a stainless steel panel back, and a back cover made of shock resistant fine resin embedded with glass fibers, it provides a high level of resistance to dust and mud. The bezel also uses three layers of fine resin with carbon fiber