GA-100-1A1

The Casio G-Shock GA-100-1A1 is a popular, highly durable analog-digital combination watch known for its matte “matte black blackout” tactical aesthetic. Part of G-Shock’s X-Large series, it matches extreme physical resistance with highly practical stopwatch and speed-tracking metrics.

Key Specifications & Design Dimensions: 55.0 mm × 51.2 mm × 16.9 mm case size. Weight: 70 grams, distributing evenly over a wide band for all-day comfort.

Material: High-durability resin case, bezel, and strap built with a scratch-resistant mineral glass crystal.

Colorway: Stealth matte black design accented with high-contrast light silver analog hands.

Operation: Over-sized, anti-slip push buttons for effortless operation even when wearing gloves or in wet environments.

Core Technical Features

Triple Protection: Engineered with absolute shock resistance, magnetic resistance (JIS Class 1), and a 200-meter water resistance rating suitable for swimming and water sports.

Advanced Chronograph: Includes a 1/1000-second precision stopwatch featuring lap/split times and a built-in speedometer display.

World Time: Tracks 29 different time zones across 48 major global cities.

Time Management: Outfitted with 5 daily alarms (including 1 snooze alarm), a 24-hour countdown timer, and an hourly time signal.

Illumination: Features an amber LED Auto-Light switch that activates automatically when you tilt your wrist toward your face.

Power Supply: Runs on a single CR1220 coin battery with an approximate 2-year lifespan.

User Considerations Legibility Pros & Cons: While the contrast of the light silver hands against the dark face makes standard analog timekeeping incredibly easy to read, the digital negative sub-dials can be challenging to decipher in low light or direct, intense sunlight.

The LED Light: The amber LED light illuminates the analog hands well but does not directly backlight the digital display panels.