USR Mainspring for Waltham 0s Model 1907, Factory No. 2230 - Steel

USR steel mainspring for Waltham 0s Model 1907 movements, Factory No. 2230, steel, new in very frail envelope. See images for further details. 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 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.