■ Product Overview
The CASIO G-SHOCK GA-2100-4A is a red analog-digital watch featuring the distinctive octagonal design of the 2100 Series.
Its slim profile combines G-SHOCK shock resistance with a Carbon Core Guard structure. Multiple shades of red are used throughout the case, dial, hands, digital display, buckle, and other exterior components.
■ Key Features
Carbon Core Guard Structure
A carbon fiber-reinforced resin inner case provides strength while keeping the watch slim and lightweight.
Shock-Resistant Construction
Designed to withstand shocks and vibrations associated with everyday and active use.
Analog-Digital Display
Combines analog hour and minute hands with a digital display for timekeeping and additional functions.
Neobrite Luminous Hands
Neobrite luminous coating is applied to the hands to improve visibility after exposure to light.
Super Illuminator
Double white LED illumination lights both the analog dial and digital display. Illumination duration can be set to approximately 1.5 or 3 seconds.
200-Meter Water Resistance
Provides 20-bar water resistance for everyday use and water-related activities, subject to the precautions in the instruction manual.
World Time
Displays the time in 48 cities across 31 time zones, plus Coordinated Universal Time. Daylight-saving time can be enabled or disabled.
Stopwatch and Countdown Timer
Includes a 1/100-second stopwatch with elapsed-time, split-time, and first/second-place measurement. The countdown timer supports settings of up to 24 hours.
Five Daily Alarms
Includes five daily alarms and an hourly time signal.
Hand Shift Function
Temporarily moves the hands away from the digital display to improve visibility.
■ Product Details
Brand: CASIO
Series: G-SHOCK 2100 Series
Model Number: GA-2100-4A
Display: Analog-Digital
Movement: Quartz
Color: Red
Case and Bezel Material: Carbon Fiber-Reinforced Resin and Resin
Band Material: Resin
Glass: Mineral Glass
Construction: Shock Resistant, Carbon Core Guard
Water Resistance: 200m / 20 Bar
Neobrite: Equipped
Light: Double LED Super Illuminator
LED Color: White
Case Dimensions: Approximately 48.5 × 45.4 × 11.8mm
Weight: Approximately 51g
Compatible Wrist Size: Approximately 145–215mm
Battery: 2 × SR726W Silver Oxide Batteries
Approximate Battery Life: 3 Years
Accuracy: Approximately ±15 Seconds per Month
Calendar: Full Auto Calendar to 2099
Time Format: 12/24-Hour
Condition: New
■ Main Functions
World time for 31 time zones
1/100-second stopwatch
24-hour countdown timer
Five daily alarms
Hourly time signal
Hand shift function
Button-operation tone on/off
Full auto calendar
Double white LED illumination
Day and date display
■ Set Contents
1 × CASIO G-SHOCK GA-2100-4A Watch
Instruction Manual and Included Documentation
Original Product Packaging
Included documentation, packaging, and warranty coverage may differ according to the product’s intended sales region.
■ Important Notes
This listing is for the red GA-2100-4A model. Other GA-2100 color variations are separate products.
GA-2100-4AJF is the Japanese domestic model notation. The suffix printed on the product, packaging, or documentation may differ according to the intended sales region.
This is a new product. It is not pre-owned, renewed, used, or refurbished.
Neobrite is a luminous coating that stores light and glows temporarily in dark conditions. Its brightness and duration depend on the amount and duration of prior light exposure.
The 200-meter water-resistance rating does not mean that the watch is certified as a professional diving instrument. Follow the included instructions and do not operate the buttons underwater unless expressly permitted.
Battery life is an approximate value and varies according to alarm, illumination, and other operating conditions.
Product colors may appear different depending on lighting and display settings.
Specifications, packaging, and included documentation may change without prior notice.