Hamilton Factory Mainspring for 6/0s Hamilton No. 717200 - Alloy

Hamilton Factory  Mainspring for 6/0s Movements, Factory No. 717200, alloy, new in very frail or torn envelope. See image for precise characteristics. These are basically equivalent to the 2521 in steel and are also known by the old Hamilton #27432. I likely have several of these so the one you get may differ slightly from the images (including one where the envelope was printed backwards). Note - these sell as fast as I list them. 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 marginally adequate job of representing the item.