NuTemper Mainspring #731 for Hampden 8/0s movements No. 15696 - Steel

NuTemper Mainspring #731 for Hampden 8/0s movements, Factory No. 15696, steel, new in frail 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.