NuVigor Mainspring #321 for Illinois 6/0s No. 47365 - Steel

NuVigor Mainspring #321 for Illinois 6/0s, Factory No. 47365, steel, new in envelope - some of which are quite fragile and torn. See images for precise mainspring specifications. I likely have several of these so the one you get may differ slightly from the images. I specialize in hard to find watch parts and all watch parts are unconditionally guaranteed. Images do an adequate job of representing the item.