G-SHOCK GBM-2100A-8B - Metal-Clad Octagon
G-SHOCK GBM-2100A-8B - Metal-Clad Octagon
A silver face behind a silver bezel is the version of this watch that looks least like a G-SHOCK and behaves exactly like one.
The GBM-2100A sits in the 2100 Series as its solar and Bluetooth model, with a stainless steel bezel over a bio-based resin case and a band of biomass plastics. Tough Solar removes the battery change entirely, and mobile link pairs it to the CASIO WATCHES app, which is what keeps a quartz watch honest over years rather than months.
Silver face, black band, 49.3 by 44.4 mm and 11.9 mm deep, 72 grams. The two analog hands run over the digital display and shift clear on demand, with Neobrite markers and a double LED lighting both. Module 5729 holds world time across 38 zones, a stopwatch, a countdown timer and alarms, accurate to fifteen seconds a month without the phone. 200 m water resistant.
Bright, light and entirely maintenance-free. Wears far smaller than the spec sheet suggests.
Perfect for: silver dial G-SHOCK watches, solar connected watches, light steel bezel analog-digital watches.
Specifications
- Collection
- 2100 Series
- Case Diameter
- 44.4 mm
- Case Thickness
- 11.9 mm
- Case Material
- Bio-based Resin / Stainless steel
- Crystal
- Mineral Glass
- Water Resistance
- 200 m (20 ATM)
- Dial Color
- Silver
- Movement
- Solar
- Caliber
- Casio module 5729
- Functions
- World time, Stopwatch, Countdown timer, Alarm, Auto calendar, Bluetooth, Solar charging
- Strap / Bracelet
- Resin Band (Biomass plastics)
- Strap Color
- Black
- Reference
- GBM-2100A-8B
- Released
- 2025-09-16
- Case Size
- 49.3 x 44.4 x 11.9 mm
- Weight
- 72 g
- Finish
- Neobrite
- Construction
- Shock Resistant
- Band Size
- 145 to 215 mm
- Power
- Tough Solar (Solar powered)
- Accuracy
- ±15 seconds per month (with no mobile link function)
- Time Adjustment
- Bluetooth: Connects to a smartphone and automatically adjusts the time
- Calendar
- Full auto-calendar (to year 2099)
- Smartphone Link
- Mobile link (Wireless linking using Bluetooth®)
- Illumination
- Double LED light LED 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 Time
- World time 38 time zones (38 cities + coordinated universal time), auto summer time (DST) switching, home city/world time city swapping
- Stopwatch
- 1/100-second stopwatch Measuring 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, lap/split time
- Timer
- Measuring unit: 1 second Countdown range: 60 minutes Countdown start time setting range: 1 second to 60 minutes (1-second increments and 1-minute increments)
- Alarm
- 5 daily alarms; Hourly time signal
- Other Features
- Hand shift feature (Hands move out of the way to provide an unobstructed view of digital display contents.); 12/24-hour format; Date/month display swapping; Day display (days of the week selectable in six languages); Analog: 2 hands (hour, minute (hand moves every 20 seconds)), 1 dial (battery level, mode) Digital: Hour, minute, second, pm, month, date, day