1955 – 1967
Specifications
| Lignes | 13.25 ‴ |
|---|---|
| Mounting Diameter | 30 |
| Thickness | 4 |
| Frequency (vph) | 18,000 |
| Jewels | 17 |
| Power Reserve | 43 |
| Hand Sizes | 1.4, 0.75, 0.20 |
| Complication | Subsidiary Seconds |
| Power | Manual |
| Shape | Round |
| Size | Large |
Notes
First mass produced Longines chronometer, Chronometer version have a higher level of finishing