The Casio G‑Shock GD0101A1ER is a tough and reliable digital watch built with Carbon Core Guard shock resistance and 200 m water resistance, perfect for everyday wear and outdoor activities. It features world time (31 zones), 1/100‑sec stopwatch, 24‑hour countdown timer, and 5 daily alarms to keep you on schedule. The Super Illuminator LED backlight ensures easy reading in low light, while the full auto calendar (to 2099) and 12/24‑hour format add practical convenience. Powered by a long life 10 year battery, this rugged G‑Shock blends classic digital style with durable functionality.Basic informationCase dimensions : 4.9 × 51.9 × 16.1 mmWeight : 65 gCase and bezel material : Bio-based Carbon/Bio-based ResinStrap : Bio-based resin strapStructure : Shock resistant , Carbon Core Guard StructureWaterproof : Waterproof up to 20 barPower and battery life : Approximate battery life: 10 years with CR2025ExternalGlass : Mineral glassAdjustable strap : From 145 to 215 mm Watch FeaturesWorld Time: 31 time zones (48 cities), home/world city switching, 4 multi-time display.Alarms & Signals: 5 daily or single alarms, hourly time signal, button tone on/off.Display & Light: White Super Illuminator LED backlight with auto light and afterglow.Calendar & Timekeeping: Full auto-calendar to 2099, 12/24-hour format, ±15 sec/month accuracy.