NuTemper Mainspring #645 for Hamilton 8/0s movements #7221 - Steel

NuTemper Mainspring #645 for Hamilton 8/0s movements, Factory No. 7221, steel, new in envelope. See image 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.