Zenith 18.5''' , Balance staff, DCN: 988
Tax included.
- DCN no: 988
- Fits cal: 18.5''' ancien & nouveau
- A: 463
- B: 227
- F: 72
- G: 121
- H: 52
Versions with positive setting mechanism.
- 18-28-3A: Breguet hair spring.
- 18-28-3A-6: Pare-chocs.
- 18-28-3P: Breguet hair spring.
- 18-28-3P-6: Pare-chocs.
- 18-28-3P-7: Breguet hair spring, swan neck regulator.
Versions with negative setting mechanism, nouveau
- 18-28-1T: Lépine.
- 18-28-3T: Lépine.
- 18-28-2T: Savonette.
- 18-28-4T: Savonette.
- 19-28-1T: Lépine grandeur 19'''
- 18-28-2T: Savonette grandeur 19'''
Versions with negative setting mechanism, ancien
- 18.5''' NVS Bas VS: Lépine and savonette, no engraved cal. no.