ZENITHNivaflex automatic mainsprings for wristwatchesNivaflex mainsprings from Boley for automatic winders. Products namewidthØcalibrethicknessitem No.0660x1.0210.0ZENITH ELITE 660, 670, 680-6850,118995007716600400x1,2212.0ZENITH EL PRIMERO 400, 30190.146995007714003141x1.2510.0ZENITH 2522P+PC, 2572PC0.11582031410