LONGINES 501 - 508
Versions: 19800 A/h:
- 501: date.
- 503: day, date.
- 505: quickset date.
- 507: day, quickset date.
Versions: 21600 A/h, micrometer regulator:
- 506: quickset date.
- 508: day, quickset date.
Versions: 19800 A/h:
Versions: 21600 A/h, micrometer regulator: