Hamilton Factory Mainspring No. 3328 for 12s 17j - Steel

Hamilton Factory Mainspring for 12s 17 Jewel Movements, Factory No. 3328, steel, new in frail envelope. See image for precise characteristics. I likely have quite a few of these so they one you get may differ slightly from the images. 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.