Hampden 12s Mainspring No. 6696 Made by Waltham - Steel

Hampden 12s Mainspring Factory No. 6696 made by Waltham, steel, new in envelope. See images for further details. Waltham didn't mark them except for "Unit Resilient Main Spring." I specialize in hard to find watch parts and all watch parts are unconditionally guaranteed. Images do an adequate job of representing the item.