HR Mainspring SA434 for Illinois 6/0s Factory No. 47371 - Alloy

HR Mainspring SA434 for Illinois 6/0s movements, Factory No. 47371, alloy, new in envelope. See image for further details. 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 all watch parts are unconditionally guaranteed. Images do a pretty good job of representing the item.