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Hamilton 21
Basic Information
| Name | Hamilton 21 |
|---|---|
| Alternative Name | ETA 2442 |
| Base Calibre | ETA 2442 |
| Manufacturer | Hamilton |
| Launch Year | 1960 |
| Is COSC certified | No |
Timegrapher
Beat rate
21,600 bph
Frequency
3 Hz
Reference: healthy amplitude ≈ 270–315° fully wound (>200° at 24 h); beat error ideally < 0.5 ms.
Technical Details
| Lignes Dimensions | 6 ‴ |
|---|---|
| Dimensions | 13.75 mm |
| Height | 3.2 mm |
| Further Measures | Mounting Diameter (Dm): 13.5mm Stem height (T): 1.6mm Mounting Height (F): 0.8mm |
| Power Reserve | 41 hours |
| Frequency | 21,600 vph |
| Jewels | 17 |
Complications and Specifications
| Shape | Round |
|---|---|
| Shock Protection | Incabloc |
| 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 | 1.00 x 0.50mm |
|---|---|
| Hand Count | 2 |
| Country Of Manufacture | Switzerland |
| Notes | Remarks: early fixed (Fig.1), later mobile stud carrier (Fig.3) indirectly driven minute allows a very big balance differences not known between 21, 211 Other data: balance staff: U2753 stem: W2771 mainspring / battery: 1.43 x 5.5 x 0.0625 x 201mm |
| Signature | 1-2) ca. 1960: 34, 17 Jewels - DWH (WH in D), Patented; Incabloc (ETA 2442) 3-4) ca. 1965: BP, Swiss, Swiss, 17 Jewels - Patented; Incabloc (ETA 2442) |
| Import Codes |
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Compatible Parts
243 other caliber(s) share compatible parts with this caliber.
61 compatible part(s) available — Supporter feature.
Metadata
| Created At | Sep 15, 2023 |
|---|---|
| Updated At | May 26, 2026, 4:43:50 AM |
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