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G-Shock GA-2100 GA-2100-1A1 black dial front view

Casio G-Shock · Manufacturer image

G-Shock · Analog-Digital

G-Shock GA-2100

GA-2100-1A1

The octagonal G-Shock that made the line wearable with a jacket: 11.8 mm, carbon-reinforced resin and 200 m of shock-proof water resistance.

Typical street price

$99

Our editorial estimate, not a live retailer price.

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At a Glance

  • Quartz movement — ±15 seconds per month (Casio specification)
  • Date display
  • Day of the week
  • World time
  • Alarm
  • Chronograph sub-dials
  • Digital display with backlight

Specifications

Brand
G-Shock
Collection
Analog-Digital
Movement
Casio module 5611, caliber 5611, battery, approximately 3 years of power reserve, rated ±15 seconds per month (Casio specification)
Case
Carbon Core Guard resin, 45.4 mm diameter, 11.8 mm thick, 48 mm lug-to-lug
Crystal
Mineral
Bracelet / strap
Integrated resin strap, Pin buckle, Integrated
Water resistance
200 m (656 ft)
Dial colours
Black
Style
Sport, Everyday, Digital
Recommended wrist
Small, Medium, Large
Country of origin
Japan

What we like

  • 11.8 mm — by far the slimmest G-Shock case
  • Carbon Core Guard construction with 200 m water resistance
  • 51 g, light enough to sleep in
  • Analog hands plus a digital display without visual clutter

Full specifications

Brand
G-Shock
Model
GA-2100
Reference
GA-2100-1A1
Collection
Analog-Digital
Typical street price
$99
MSRP
$99
Movement type
Quartz
Movement
Casio module 5611
Caliber
5611
Power reserve
Battery, approximately 3 years
Stated accuracy
±15 seconds per month (Casio specification)
Balance spring
Not published
Case diameter
45.4 mm
Case thickness
11.8 mm
Lug-to-lug
48 mm
Lug width
Integrated
Weight
51 g
Case material
Carbon Core Guard resin
Crystal
Mineral
Water resistance
200 m (656 ft)
Dial colours
Black
Bracelet / strap
Integrated resin strap
Bracelet material
Resin
Clasp
Pin buckle
Date
Yes
GMT
No
Chronograph
Yes
Style
Sport · Everyday · Digital
Recommended wrist
Small · Medium · Large
Country of origin
Japan
Released
2019
Selection Score
Not published
Watch Size Database

Where to Buy

Selection Time is reader-supported. If you buy through a link on this page we may earn a commission. This never affects our scores or what we recommend.

Watch Brands: G-Shock

G-Shock is Casio's shock-resistance programme, launched in 1983 around a single requirement: survive a ten-metre drop. Four decades later it remains the reference for durability at any price.

All watches from G-Shock

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