OmegaNivaflex automatic mainsprings for wristwatchesNivaflex mainsprings from Boley for automatic winders. Products namewidthØcalibrethicknesslengthitem No.2371x0.956.5OMEGA 670, 671, 680 - 6820.07240820237102373x0.956.5OMEGA 683, 684, 6850.081-820237302378x0.9511.5OMEGA 10100.125009650101012082379x0.9511.5OMEGA 10000.153409650100012082450x1.0010.0OMEGA 5700.10532082024500550x1,0110.0OMEGA 550 - 552, 751, 7520.11380965055012081040x1.0512.0OMEGA 1040, LEM 13450.13500965010401208730-12081.105,85OMEGA 73096507301208330x1.109.0OMEGA 330, 3410.095340820260502944x1,2012.0OMEGA 1045, LEM. 51000.106590965010451208860-12081.3010.5OMEGA 860, 3600.11542096508601208