G-Shock Watch MT-G Bluetooth Smart MTG-B2000D-1AER. These new lightweight metal models, with newly advanced shock resistant structures, are the latest additions to the MT-G lineup that packs the latest that technology has to offer into shock resistant designs that combine metal and resin materials.A Carbon Core Guard structure combines with the Metal Core Card structure to create a new Dual Core Guard structure, which houses a module protected by an integrated carbon monocoque case and exterior metal parts. The metal frames have a new type of slide lever mechanism that makes band replacement quicker and simpler, and metal is also used for the outer case sides. The bezel is a piece that is separate from the metal frame, which enables greater coloring versatility. The elegantly attractive mirror finish of the exterior metal parts gives these watches their distinctive look. The elegance of these models is further enhanced by high transparency sapphire crystals, as well as hour markers and inset dials that are precision engraved at the CASIO Yamagata Factory.Functionwise, these models maintain constant Bluetooth connection with a smartphone running the G-SHOCK Connected app to obtain accurate time information from an on-line time server for automatic time adjustment, even if you move between time zones. MULTIBAND 6 automatically adjusts time settings based on reception of one of six calibration signals around the globe when you are within the range of a signal, even if connection with a smartphone is not possible, for accurate timekeeping no matter where your travels take you. Other basic features include high brightness LED illumination, World Time, stopwatch, and more. Stable operation is ensured by a CASIO original Tough Solar charging system.