Swartchild Black Shield Mainspring #4364 for Elgin 6s No. 824 - Steel

Swartchild Black Shield Mainspring #4364 for Elgin 6s, 7j, Factory No. 824, steel, new in 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 and all watch parts are unconditionally guaranteed. Images do a pretty good job of representing the item.