Washington Mainspring for 16s Hamilton No. 317 - Steel

Washington Resilient Mainspring for 16s Hamilton Movements, Factory No. 317, new in really cool envelope. See images for precise mainspring specifications. I likely have several of these so the one you get may differ slightly from the images. I specialize is hard to find watch parts and all watch parts are unconditionally guaranteed. Images do a pretty good job of representing the item.