Mechanics 3 min read
The simple science of quartz watches
Learn how a battery, a tiny crystal and a simple circuit work together to keep your quartz watch running with highly reliable accuracy every day.
G-Shock · Classic Style
Youth
Ref. GA21009A9
Watch details and strap advice
- Case diameter
- 45.4 mm
- Case height
- 11.8 mm
- Case material
- Resin / Plastic
- Case shape
- Octagonal
- Water resistance
- 200 m
- Movement
- Quartz
- Dial
- Green
The G-Shock Youth takes a 26 mm strap: measure between the lugs and that is the only number you need. Built for water, it wears naturally on rubber or a nylon NATO; a leather strap keeps it for dry days. With a 45.4 mm case and 200 m of water resistance, a thicker strap balances the case. Quartz movement. Most straps here come with quick-release spring bars, so the swap takes a minute and no tool.
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