NuVigor Mainspring #312 for Illinois 12s movements No. 47343 - Steel

NuVigor Mainspring #312 for Illinois 12s movements, Factory No. 47343, steel, new in distressed envelope. 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 is hard to find watch parts and all watch parts are unconditionally guaranteed. Images do a pretty good job of representing the item.