Sandsteel Mainspring for Illinois 12s Factory No. 47350 - Steel

Sandsteel Mainspring for Illinois 12s, Factory No. 47350, steel, new in possibly frail and/or dirty envelope. See image for further details and precise mainspring specifications. I likely have several of these so the one you get may differ slightly from the images. I specialize is hard to find watch parts and all watch parts are unconditionally guaranteed. Images do a marginally adequate job of representing the item.