Montre Casio GA-100-1A4ER

The Casio GA-100-1A4ER is a durable analogue-digital wristwatch with a resin case and band, mineral glass and a CR1220 battery providing about two years of operation. It combines shock and magnetic resistance with world time, stopwatch, countdown timer, multiple alarms and a bright LED illumination with Auto Light Switch for convenient reading of the display. Lightweight and compact, it is suitable for everyday wear and outdoor activities.

Advantages

Shock-resistant construction and magnetic shielding protect internal components from impacts and magnetic fields. The Auto-LED light improves legibility in low light, while mineral glass resists scratches. Long battery life (approx. 2 years) and a 20 bar (200 m) water resistance rating allow use during water activities. Multiple timing functions — world time, 1/1000 sec stopwatch up to 100 hours, 24-hour countdown timer with auto-repeat, five daily alarms and snooze — provide flexible time management.

Suitable for

Key specifications

How to use

Set the time, date and desired alarms using the watch’s mode and adjust buttons following the user manual. Use the mode button to switch between timekeeping, world time, stopwatch and timer functions. Activate the Auto Light Switch if you need the display to illuminate when the watch is tilted toward your face. For swimming or snorkeling, ensure the crown and buttons are properly secured before exposure to water.

Recommendations

Avoid exposing the watch to strong chemicals, solvents or prolonged direct sunlight. Have the battery replaced by an authorised service centre to maintain water resistance and check seals after battery change or heavy impacts.