ZENITHNivaflex automatic mainsprings for wristwatchesNivaflex mainsprings from Boley for automatic winders. Products namewidthØthicknesslengthcalibreitem No.0660x1.0210.00,118405ZENITH ELITE 660, 670, 680-685995007716600400x1,2212.00.146490ZENITH EL PRIMERO 400, 3019995007714003141x1.2510.00.115315ZENITH 2522P+PC, 2572PC82031410