Sandsteel Mainspring for Illinois 6/0s #47363 - Steel

Sandsteel Mainspring for Illinois 6/0s movements, Factory No. 47363, steel, new in envelope. See images for precise mainspring specifications 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 guaranteed. Images do a pretty good job of representing the item.