HR Mainspring SA436 for 18/0s Illinois Factory No. 47384 - Alloy

HR Mainspring SA436 for 18/0s Illinois, Factory number 47384, T-Brace end, alloy, new in 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 is hard to find watch parts and all watch parts are unconditionally guaranteed. Images do a pretty good job of representing the item.