Carbon Core Guard structureEver 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.High-strength resin material, which is reinforced with carbon fibers, makes it possible to create a case that is a mere 11.8 mm thin, which is the thinnest among G-SHOCK combination models.Neobrite: Only for GA-2100-1A, GA-2100-4ACarbon Core Guard StructureA new carbon core guard structure protects the module by enclosing it in a carbon case. The case is made of fine resin embedded with carbon fibers for outstanding strength and crack resistanceSpecificationsCase / bezel material: Carbon / Resin　Resin BandShock ResistantMineral Glass200-meter water resistanceDouble LED lightLED light for the face (Super illuminator, selectable illumination duration (1.5 seconds or 3 seconds), afterglow)LED backlight for the digital display (Super illuminator, selectable illumination duration (1.5 seconds or 3 seconds), afterglow)World time31 time zones (48 cities + coordinated universal time), daylight saving on/off, Home city/World time city swapping1/100-second stopwatchMeasuring capacity:00'00''00~59'59''99 (for the first 60 minutes)1:00'00''~23:59'59'' (after 60 minutes)Measuring unit:1/100 second (for the first 60 minutes)1 second (after 60 minutes)Measuring modes: Elapsed time, split time, 1st-2nd place timesCountdown timerMeasuring unit: 1 secondCountdown range: 24 hoursCountdown start time setting range: 1 second to 24 hours (1-second increments, 1-minute increments and 1-hour increments)5 daily alarmsHourly time signalHand shift featureFull auto-calendar (to year 2099)12/24-hour formatButton operation tone on/offRegular timekeepingAnalog: 2 hands (hour, minute (hand moves every 20 seconds)), 1 dial (day)Digital: Hour, minute, second, pm, month, dateAccuracy: ±15 seconds per monthApprox. battery life: 3 years on SR726W × 2Size of case / Total weightSize of case : 48.5×45.4×11.8mmTotal weight : 51g