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Hamilton 987A
Basic Information
| Name | Hamilton 987A |
|---|---|
| Manufacturer | Hamilton |
| Launch Year | 1937 |
| Caliber Family | Description 987: set jewels, bimetallic balance 987F: friction fit jewels 987E: Elinvar hairspring, monometallic balance 987A: bridge layout and many parts redesigned 987S: sweep second Related calibers Hamilton 987A |
| Is COSC certified | No |
Technical Details
| Lignes Dimensions | 11.26 ‴ |
|---|---|
| Dimensions | 25.4 mm |
| Height | 4.15 mm |
| Further Measures | : 6 Mounting Diameter (Dm): 24.8mm Stem height (T): 1.8mm Mounting Height (F): 0.4mm |
| Power Reserve | 38 hours |
| Frequency | 18,000 vph |
| Jewels | 17 |
Complications and Specifications
| Shape | Round |
|---|---|
| Complications |
|
| Regulator Type | Pinned Regulator (or Index Regulator) |
| Movement Type | Manual |
| Escapement Type | Swiss Lever |
| Control Type | Balance Wheel |
| Winding Type | Stem Winding (Crown) |
| Setting Type | Stem Set (Crown Pull) |
Additional Information
| Hand Sizes | 1.45 x 0.76 / 0.16mm |
|---|---|
| Hand Count | 3 |
| Country Of Manufacture | (not set) |
| Notes | Remarks: 1937-1948, 486300 Breguet hairspring Other data: balance staff ronda: 1206 (6/0) |
| Signature | 1946: O382457, Hamilton, U.S.A., 987A, 17 Jewels |
| Import Codes |
|
Metadata
| Created At | Sep 15, 2023 |
|---|---|
| Updated At | Apr 23, 2025, 11:32:56 PM |
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