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.
Seiko
SRPG39K1
Ref. SRPG39K1
Watch details and strap advice
- Case diameter
- 39.4 mm
- Case material
- Stainless Steel
- Water resistance
- 100 m
- Movement
- Automatic
- Caliber
- Seiko 4R36
- Dial
- Blue
The Seiko SRPG39K1 takes a 20 mm strap: measure between the lugs and that is the only number you need. We list 37 straps in that width. With a 39.4 mm case and 100 m of water resistance, a strap of medium thickness keeps the balance. Automatic movement. Most straps here come with quick-release spring bars, so the swap takes a minute and no tool.
Straps by lug width (20 mm) 37
All 37 20 mm strapsWidth is a starting point. Check the case and end fittings before choosing.
-
Heritage CuffLeather€27.90 -
Slim Colour LeatherLeather€24.90 -
Rivet RallyLeather€49.90 -
Dense Mesh SteelSteel€34.90 -
Diagonal WeaveNylon€24.90 -
Regatta StripeNylon€22.90 -
Ladder Link SteelSteel€39.90 -
Camouflage Five RingNylon€27.90 -
Square Slot SiliconeSilicone€22.90 -
Air Sport SiliconeSiliconeAs low as €22.90 -
Vintage RallyLeather€34.90 -
Denim StitchNylon€22.90
Read before you choose
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