Mainspring for Forster 420
Height, diameter, thickness and length
📏 Mainspring dimensions
| GR no. | Height | Diameter | Thickness | Length | Type |
|---|---|---|---|---|---|
| 2780 | 1.15 mm | 6.5 mm | 0.08 mm | 200 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 88.
🛒 Matching mainspring in our shop
Only mainsprings with exactly the same height, thickness and length are shown; the diameter is equal or up to 1 mm smaller – a smaller spring settles in the barrel.
🔗 According to the catalogue, the same mainspring (GR 2780) also fits
❓ Frequently asked questions
Which mainspring fits the Forster 420?
According to the Générale Ressorts catalogue (height × diameter × thickness × length): 1.15 × 6.5 × 0.08 × 200 mm (GR 2780, hand-wound, normal end hook).
Is this mainspring available in the shop?
Yes, Master Watch Parts currently has 1 matching mainsprings in stock.
Which other calibers use mainspring GR 2780?
According to the catalogue also in Eterna 1031, Eterna 1033 à 1034 S, Forster 400, Forster 412, Gruen 270 and 10 other calibers.
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