Newall Security Mainspring #663 for 11/0s Hampden Movements #11696 - Steel

Newall Security Mainspring #663 for 11/0s Hampden Wrist Watch movements, factory number 11696, steel. Could also very well fit in other small American wrist watches too. 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.