Mainspring for Rolex 10 '/2 Speed King

Height, diameter, thickness and length

1.50 × 8.5 × 0.10 × 280 mmheight × diameter × thickness × length

Note: We have transcribed this information to the best of our knowledge from the Générale Ressorts mainspring catalogue (GR 2, 1974). All information has been carefully checked but is provided without guarantee. Please check yourself before fitting that the mainspring fits, in particular height, diameter, thickness and length.

📏 Mainspring dimensions

GR no.	Height	Diameter	Thickness	Length	Type
4121	1.50 mm	8.5 mm	0.10 mm	280 mm	Hand-wound, normal end hook

All dimensions in millimetres. The height of a mainspring is often also called its “width”. Source: Générale Ressorts, mainspring catalogue GR 2 (March 1974), page 167.

🔗 According to the catalogue, the same mainspring (GR 4121) also fits

❓ Frequently asked questions

Which mainspring fits the Rolex 10 '/2 Speed King?

According to the Générale Ressorts catalogue (height × diameter × thickness × length): 1.50 × 8.5 × 0.10 × 280 mm (GR 4121, hand-wound, normal end hook).