NuVigor Mainspring #239 for Hamilton 0s Factory No. 1536 - Steel

NuVigor Mainspring #239 for Hamilton 0s, Factory No. 1536, Steel, new in possibly distressed envelope. See image for precise characteristics. 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 regardless of how it may look, all watch parts are unconditionally guaranteed. Images do a pretty good job of representing the item.