Comsco Mainspring #1133 for Illinois 16s Factory No. 47333A - Steel

Comsco Mainspring #1133 for Illinois 16s movements, Factory No. 47333A, steel, new in envelope. See images for precise mainspring specifications and other useful details. 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.