Nu Vigor Mainspring No. 73B – 1.40 x 0.07 x 24.13 mm – Dennison 5 x 14

Description:
Vintage Nu Vigor mainspring No. 73B, made in Switzerland. A high-quality Swiss replacement mainspring designed to “add new life to the watch,” providing excellent strength, flexibility, and consistent torque delivery. Suitable for small to mid-sized wristwatch movements.

Specifications:

• Brand: Nu Vigor
• Part No: 73B
• Width: 1.40 mm
• Strength: 0.07 mm
• Length: 24.13 mm (9½ inches)
• Dennison: 5 x 14
• Material: Tempered Swiss alloy steel
• End Type: Tongue end
• Condition: New old stock (NOS), unused, sealed in original wax envelope

Condition Note:
This is new old stock (NOS) — unused and sealed in its original paper and wax packaging. Envelopes show light age discolouration and handling marks. The mainspring remains bright and clean.
Listing is for one mainspring; multiples available.

Summary:
Original Nu Vigor mainspring No. 73B, Made in Switzerland, ideal for vintage wristwatch movements requiring a 1.40 mm width spring. Precision-made for professional watchmakers and collectors restoring classic Swiss or American wristwatches.

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