Marco Mainspring #3061 for Alpina 490, Belforte 11C, ETA 735, Cortebert 635 - Steel

Marco steel mainspring #3061 for Alpina 490, Belforte 11C, ETA 735, Cortebert 635 caliber movements and quite likely many others. See images for precise mainspring specifications. I specialize in hard to find watch parts so I usually have whatever you might need and all watch parts are unconditionally guaranteed. Images do a pretty good job of representing the item.