Carbon Core Guard structure: Ever since the first DW-5000C went on sale back in 1983, G-SHOCK has continued to push the limits of timekeeping toughness while creating new and original designs. These new models embody these efforts in an attractively thin configuration. These new models inherit the octagon form that was also employed for the original DW-5000C. Analog-digital timekeeping comes packed into a no-nonsense simple design without sacrificing G-SHOCK level toughness.