Mechanics 8 min read
How an automatic watch works
Your wrist gives it energy. A spring saves it. A tiny balance sets the rhythm. Follow the journey inside an automatic watch, one pencil drawing at a time.
Zenith · Defy
Defy El Primero 21 Chroma
Ref. 4990109004/01R947
Watch details and strap advice
- Case diameter
- 44 mm
- Case height
- 14.5 mm
- Case shape
- Round
- Water resistance
- 100 m
- Movement
- Automatic
- Caliber
- El
- Dial
- Skeleton
The Zenith Defy El Primero 21 Chroma takes a 23 mm strap: measure between the lugs and that is the only number you need. With a 44 mm case and 100 m of water resistance, a thicker strap balances the case. Automatic movement. Most straps here come with quick-release spring bars, so the swap takes a minute and no tool.
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