From Casio G-Shock, the innovators of tough timekeeping, comes the GGB100 Master of G Mudmaster watch series that has been designed to endure the toughest environments. This watch features a carbon core guard structure case, in black with grey accents, that allows the internal mechanics of the watch to be protected from shock-induced damage. This watch is mud resistant with metal buttons that form a tight seal on the case, a dual back cover that consists of a stainless steel panel back and an outer cover made of shock resistant fine resin embedded with glass fibers, and the bezel has three layers of fine resin with carbon fiber inserts. The Quad Sensor capabilities provide instant access to a compass, altitude/barometer, thermometer, and an accelerometer that keeps track of your step count. Additionally, this watch connects via Bluetooth to a special G-Shock app that helps with the configuration, as well as records altitude data, route information, and step counts. These recordings are used to create an activity log you can use for tracking. Mode Switching Customization allows you to turn on and off individual modes and their sequence, for a personalized feel. This capable watch is finished with a olive green resin band.Features of this highly functional watch include:Shock ResistantMud ResistantCarbon Core Guard structure200 meter water resistanceOlive green resin bandCarbon and resin caseNeobriteDouble LED lightMobile link (Wireless linking using Bluetooth(R))Digital compassAltimeterAuto log data (High/low altitudes, cumulative ascent and descent)BarometerThermometerStep count using a 3-axis acceleration sensor: 0 to 999,999 step count display rangePower Saving: Auto sensor sleep state entry after fixed period of non-activityWorld time with 38 time zonesSunrise, sunset time