NuREZISTA Mainspring #654 for Hamilton 22/0s Factory No. 6221 - Steel

NuREZISTA Mainspring #654 for Hamilton 22/0s movements, Factory No. 6221, steel, new in envelope. See image for precise specifications. I specialize in hard to find watch parts and all watch parts are unconditionally guaranteed. Images do a pretty good job of representing the item.