Illinois Factory Mainspring #47301 for 18s Pocket Watches - Steel

Illinois Factory Mainspring, Factory No. 47301 for 18s movements, steel, new in frail envelope. One of the beautiful thing about factory mainsprings is that they pretty much always fit. See images for precise mainspring specifications. 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.