G-SHOCK GA-2100K-1AER

Built for everyday use

Whether you’re on patrol, dealing with incidents or just need something dependable day to day, you want a watch that works without getting in the way. The G-SHOCK GA-2100 delivers exactly that, combining a slim, low-profile build with the durability you rely on.

Tough without the bulk
Shock resistant construction and 200 metre water resistance give you the confidence to handle demanding environments. The Carbon Core Guard structure adds strength while keeping the case slim at just 11.8 mm, so you’re protected without carrying unnecessary bulk.

Lightweight, low-profile design
At only 51 g, it stays comfortable through long shifts and daily wear. It sits neatly under sleeves and kit, avoiding the usual issues that come with larger, bulkier watches.

Clear, functional display
The analogue-digital layout gives you quick time checks at a glance, with full digital functionality when needed. The hand shift feature moves the hands out of the way, so you always have a clear view of the display.

Practical features that actually get used
You get everything you need, without overcomplication:
- World time across 31 time zones
- 1/100-second stopwatch with split and lap tracking
- Countdown timer adjustable up to 24 hours
- 5 daily alarms with hourly signal
- Built for staying organised on shift, not unnecessary extras.

Visibility when it matters
Double LED lighting with Super Illuminator gives you clear visibility in low light. Separate illumination for the dial and digital display, with adjustable duration and afterglow, ensures you can read it quickly in dark conditions.

Reliable, everyday performance
A carbon and resin build, mineral glass and up to 3 years battery life mean it’s made to perform consistently without constant attention. Accuracy stays within ±15 seconds per month, so you can rely on it day in, day out.

Subtle design, off-duty appeal
Finished in a smoked, blackout style inspired by low-light environments, it keeps a clean, understated look on shift while still standing out off duty. A modern take on G-SHOCK that balances style with function.

World Time
Track time across 31 time zones (48 cities + Coordinated Universal Time), with the option to turn daylight saving on or off.

Stopwatch
1/100-second stopwatch with multiple tracking modes including elapsed time, split time and 1st–2nd place times.

Measures up to 24 hours, with precision at 1/100 second for the first 60 minutes, then 1-second intervals after.

Countdown Timer
Countdown timer with a range of up to 24 hours. Adjustable from 1 second to 24 hours, with flexible settings in seconds, minutes or hours.

Alarms & Hourly Signal
Includes 5 daily alarms plus an hourly time signal to keep you on schedule throughout the day.

Lighting
- Double LED light system with Super Illuminator.
- LED light for the face
- LED backlight for the digital display

Both feature selectable illumination duration (1.5 or 3 seconds) with afterglow for visibility in low light. White LED.

Calendar
Full auto-calendar programmed up to the year 2099 for accurate date tracking.

Mute Function
Option to turn button operation tones on or off for silent use.

Accuracy
Maintains accuracy within ±15 seconds per month.

Display Options
Switch between 12 and 24-hour formats.

Analogue and digital displays show time, date and day for quick reference.

Hand Shift Feature
Hands move out of the way when needed, giving you a clear, unobstructed view of the digital display.

Timekeeping Details
- Analogue: 2 hands (hour, minute) plus day display dial
- Digital: Hour, minute, second, pm indicator, month and date

Dimensions
Case size: 48.5 × 45.4 × 11.8 mm
Weight: 51 g

Materials
Case and bezel: Carbon / Resin
Band: Resin band

Construction
Shock resistant construction
Carbon Core Guard structure

Water Resistance
200 metres

Battery Life
Approx. 3 years (SR726W × 2)

Glass
Mineral glass

Fit
Compatible band size: 145 to 215 mm