Comsco Mainspring #1221 for 12s N.Y. Standard Factory No. 1322 - Steel

Comsco Mainspring 1221 for 12s N.Y. Standard movements, Factory No. 1322, steel, new in frail envelope. See mages for precise mainspring specifications. 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.