Sandsteel Mainspring for Illinois 16s 60hr RR No. 47309 - Steel

Sandsteel Mainspring for Illinois 16s 60hr Railroad movements, Factory No. 47309, steel, new in envelope. 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 barley adequate good job of representing the item.