Elgin Factory Mainspring for 16s No. 817 - Steel

Elgin factory mainspring for 16s movements, Factory No. 817, steel, new in a likely very frail envelope. Has the typical Elgin DB&H end. These were available in several strengths and those that I can supply are shown in the drop-down list. Elgin mainsprings are coated in very sticky grease and must be cleaned before use. See image for precise characteristics. 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.