NuREZISTA Mainspring #700 for Illinois 6/0s No. 47370 - Steel

NuREZISTA Mainspring #700 for Illinois 6/0s movements, Factory No. 47370 steel, new in a 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.