Hamilton 18s Mainspring Factory No. 14 / 718010 - Steel

Hamilton Mainspring for 18s, Factory No. 14 / 718010, steel, new in envelope. See images for further (very limited) details. While it is not marked I am confident this is a "newer" factory Hamilton mainspring. I specialize in hard to find watch parts and all watch parts are unconditionally guaranteed. Images do an adequate but perhaps somewhat incomplete job of representing the item.