HR Mainspring A428 for Illinois 0s & 3/0S Movements #47358 - Steel

HR Mainspring A428 for Illinois 0s & 3/0s movements, Factory No. 47358, steel, new in envelope. See images for further details. I may 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.