Marco Mainspring #535 for 12s Illinois Factory No. 47349 - Steel

Marco Mainspring #535 for 12s Illinois Motor Barrel 5th to 6th models, Factory No. 47349, steel, new in envelope. See images for further details. I likely have several of these so the one you get may differ slightly from the images. I specialize is hard to find watch parts and all watch parts are unconditionally guaranteed. See image for precise characteristics. Images do a pretty good job of representing the item.