Marco Mainspring #513 for 16s Illinois Factory No. 47333 - Steel

Marco Mainspring #513 for 16s Illinois 4th to 5th model movements (not 60hr), Factory No. 47333, steel, new in envelope. See images for further details. I likely have several of these so he 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 pretty good job of representing the item.