NuPower Mainspring for 18/0 Hamilton Factory No. 2721 - Steel

NuPower Mainspring for 18/0s Hamilton, Factory No. 2721, T end, steel, new in envelope. See images for precise mainspring specifications. I specialize in hard to find watch parts so I usually have whatever you might need and all watch parts are unconditionally guaranteed. Images do a pretty good job of representing the item.