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.
Certina · DS Action
Ref. C0324291804100
The Certina DS Action GMT takes a 21 mm strap: measure between the lugs and that is the only number you need. We list 6 straps in that width. Built for water, it wears naturally on rubber or a nylon NATO; a leather strap keeps it for dry days. With a 43.1 mm case and 200 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.
Width is a starting point. Check the case and end fittings before choosing.