Zenith 18.5''' , Balance staff, DCN: 988

• 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.