Description: Vintage Sterling Guaranteed Watch Mainspring, supplied for Newmark 10½ ligne wristwatch movements. Produced by Sterling of England, this mainspring offers consistent power, long service life, and reliable timekeeping for British and Swiss wristwatches of the mid-20th century.
Specifications:
Brand: Sterling
For: Newmark 10½ ligne movement
Height: 1.75 mm
Force: 0.12 mm
Length: 265 mm
Marked: “British Made – Sterling Guaranteed”
Material: Tempered spring steel
Condition: New old stock (NOS), unused, supplied with original wax envelope
Condition Note: This is new old stock (NOS) — unused and complete with its original wax-paper packaging. The packaging shows minor creasing and light ageing, and the mainspring may show slight surface tarnish from long-term storage.
Summary: Original Sterling mainspring for Newmark 10½ ligne movements, Made in England, ideal for restoring vintage British or Swiss wristwatches. A genuine NOS part from a respected mid-century manufacturer.
Shipping: As usual, this item will be packaged carefully and dispatched with tracking. International shipping is available upon request.
