Casio G-Shock GM-B2100 — Fully-Metal “CasiOak” with Bluetooth

GM-B2100D-1A — Updated August 2022 color!

GM-B2100 Model Range *may be updated

Quick Content Guide

  1. GM-B2100 Model Range *in different colors and bands
  2. General information about the watch *year of first release, model range etc.
  3. G-Shock GM-B2100 Display Guide *for key functions only
  4. G-Shock GM-B2100 on the wrist *only images and only on the wrist
  5. GM-B2100 Usage Patterns *what the watch is usually meant for
  6. Other G-Shock GA Watches *similar by price and functions but different by cases
  7. Official GM-B2100 Specs *all details and for base version GST-B400-1A
  8. Recent News about GM-B2100 *the latest breaking news and videos

General Information

*average Amazon Price, we may earn commission from purchases
Year of first Release2022
Suitable for Wrist Size150 – 205 mm
Module Number5691 / Manual
Model RangeOctagon
Battery TypeSolar (G-Shock Batteries)
Other Divisions the GA-B2100 belongs to: *you may find all watches of the division by clicking on the linkG-Shock Ana-Digi
G-Shock Bluetooth
G-Shock For Small Wrists
G-Shock Solar
G-Shock 2022

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G-Shock GM-B2100 Display Guide *for key functions only. For you to know how it works))

General Display

  1. Hour hand
  2. Minute hand
  3. Mode hand
    Indicates the current mode. In the Timekeeping mode, this hand shows the current charge level.
  4. LCD

Shifting Hands to Read the Digital Display

Hand shift moves the hands out of the way for easy viewing of display information.

Phone Finder

You can use phone finder to trigger a tone on the phone to make it easy to find. The tone is forced to sound even if the phone is in vibrate mode.

Checking World Time

Enter the World Time.
After the currently selected World Time City name appears, the watch will display the current time in that city.

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G-Shock GM-B2100 on the wrist!

GM-B2100 Usage Patterns *what the watch is usually meant for

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What we like in GM-B2100 *comments by experts with 10 years experience in writing about Casio watches
— Full-metal construction (With its screw-back case, bezel and band crafted with stainless steel, the watch offers a streamlined, minimalist design while protecting the module from drops and impacts with its iconic G-SHOCK shock-resistant structure)
Retro look (Now in a full-metal construction, this 2100-line watch features an octagonal form inherited from the DW-5000C, the very first G-SHOCK that debuted in 1983)
Tough Solar (CASIO’s original solar-charging system converts not only sunlight but also light from fluorescent lamps and other sources into power)
Mobile link (Wireless linking using Bluetooth(R)) (for time sync with your phone data)
G-SHOCK Connected App (you may manage all watch settings through your phone)
— 200-meter water resistance (good for swimming but not for deep diving)

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Other G-Shock GM Watches *similar by price and functions but different by cases

These are not all G-Shock GM Series. Here is a list of All G-Shock GM Watches →

Official Casio Description.

Introducing the first full-metal addition to the continually evolving 2100 line of timepieces that inherit the legacy of the first-ever G-SHOCK, the DW-5000C.

Luxe full-metal construction with a screw-back case, bezel, and band crafted in stainless steel creates a streamlined, minimalist design, while protecting the module from impact when dropped. We take it way back with the octagonal bezel and dimpled band design of the original from 1983, all done in metal.

High-density mounting keeps the analog-digital combination module slim, while still providing the advanced functions you love in a compact profile and comfortable fit.

Pairs with a smartphone via Bluetooth®. Simply tap into the dedicated app for precision timekeeping that keeps you on track. With Tough Solar, a high-brightness LED light and a range of other convenient functions, this is a timepiece that delivers on style and practical utility.

Official GM-B2100 Specs / Features *for base version GM-B2100D-1A

  • Case size (L× W× H): 49.8 × 44.4 × 12.8 mm
  • Case / bezel material: Stainless steel
  • Weight: 165 g
  • Band
    Stainless Steel Band
    Solid Band
    One-touch 3-fold Clasp
  • Tough Solar (Solar powered)
  • 200-meter water resistance
  • Mobile link (Wireless linking using Bluetooth®)
  • App connectivity feature
    Auto time adjustment
    Easy watch setting
    Approximately 300 world time cities
    Time & place
    Phone finder
  • Mineral Glass
  • Screw Lock Back
  • Compatible band size: 150 to 205 mm
  • Neobrite
  • World time
    38 time zones (38 cities + coordinated universal time), city code display, city name display, daylight saving on/off, 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
  • Countdown 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)
  • 5 daily alarms
  • Hourly time signal
  • Light
    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)
  • Full auto-calendar (to year 2099)
  • Battery level indicator
  • Approx. battery operating time:
    7 months on rechargeable battery (operation period with normal use without exposure to light after charge)
    18 months on rechargeable battery (operation period when stored in total darkness with the power save function on after full charge)
  • Accuracy: ±15 seconds per month (with no mobile link function)
  • 12/24-hour format
  • Date/month display swapping
  • Day display (days of the week selectable in six languages)
  • Regular timekeeping:
  • Analog: 2 hands (hour, minute (hand moves every 20 seconds)), 1 dial (battery level, mode)
  • Digital: Hour, minute, second, pm, month, date, day

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Recent News about GM-B2100 *on

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