Description: Vintage Sandalloy mainspring, made in the U.S.A. by Sandvik Steel Inc., Fairlawn, New Jersey. This premium mainspring was produced for use in Swiss watches and features Sandvik’s proprietary “Sandalloy” blend — a high-performance alloy designed to resist breakage, rust, and power loss under normal operating conditions.
Specifications:
Brand: Sandalloy (Sandvik Steel Inc.)
Reference: S6891
Width: 1.50 mm
Strength: 0.11 mm
Length: 9½ inches
Type: White alloy mainspring for Swiss watches
Marked: “Guaranteed not to break, rust or lose power under normal conditions”
Condition: New old stock (NOS), unused, supplied in original red paper envelope with wax wrap
Condition Note: This mainspring is new old stock, complete and unused. The outer red paper packet shows light age-related wear, while the wax-sealed inner wrap remains intact and well-preserved.
Summary: High-quality Sandalloy mainspring S6891, manufactured by Sandvik Steel Inc., USA, for Swiss watches. A durable, rustproof alloy spring ideal for period watch restoration or precision repair work.
Shipping: As usual, this item will be packaged carefully and dispatched with tracking. International shipping is available upon request.
