Vintage Helvetia 838 Mainspring – For Helvetia, Alpina, Certina & Felsa Calibres

Description:
Genuine vintage mainspring for Helvetia, Alpina, Certina, and Felsa automatic movements, supplied in original packaging from A.G. Thomas (Bradford) Ltd. Made in Switzerland and supplied as a genuine spare part, this high-quality new old stock mainspring is suitable for several mid-century Swiss automatic calibres.

Listing is for one mainspring only. Where multiples are available, some orders may not include the original outer packaging.

Specifications:

• Type: Automatic mainspring
• Compatible calibres:
  • Helvetia 836, 837, 838, 841
  • Alpina 664
  • Certina 25.072, 25.0721, 25.0723
  • Felsa 410, 415
• Barrel diameter: 10 mm
• Height: 1.45 mm
• Length: 320 mm
• Thickness (strength): 0.11 mm
• Material: Unbreakable Swiss steel
• Country of manufacture: Switzerland

Condition:

• New old stock (NOS) – unused and in original packaging.
• Packaging shows minor age-related wear.

Summary:
A genuine Swiss-made automatic mainspring compatible with several Helvetia, Alpina, Certina, and Felsa movements — an ideal replacement part for professional watchmakers or vintage restorers.

Postage & Shipping:
As usual, this item will be packaged carefully and dispatched with tracking. International shipping is available upon request.