Black Shield Mainspring No. 48430 1.80 x 0.10 x 11½" Dennison 9 / 11 Tongue End

Description:
Vintage Black Shield mainspring No. 48430, manufactured in Switzerland and distributed by Swartchild & Co. This premium-quality mainspring features a tongue end and is suitable for medium-to-large wristwatch or small pocket watch movements. Made from finely tempered Swiss alloy steel for reliable and long-lasting performance.

Specifications:

• Brand: Black Shield (Swartchild & Co.)
• Part No: 48430
• Width: 1.80 mm
• Strength: 0.10 mm
• Length: 11½ inches (approx. 29.2 cm)
• Dennison: 9 / 11
• End Type: Tongue end
• Material: Tempered Swiss alloy steel
• Condition: New old stock (NOS), unused, sealed in original packaging

Condition Note:
This is new old stock (NOS) — unused and sealed in original paper and wax packaging. The packaging may show age-related wear or light marks, and the mainspring may display light tarnish from long-term storage.
Listing is for one mainspring only; multiple available.

Summary:
Original Black Shield No. 48430 mainspring, made in Switzerland and distributed by Swartchild & Co., a leading American supplier of precision watch parts. Suitable for medium-sized wristwatch and small pocket watch calibres.

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