Swartchild Black Shield Mainspring for Illinois 6/0s #47365 - Steel

Swartchild & Co Black Shield Mainspring No.19802 for Illinois 6/0s movements, Factory No. 47365 (old #1422), steel, new in frail envelope. See image for further details. I likely have several of these so the one you get may differ slightly from the image. I specialize in hard to find watch parts and all watch parts are unconditionally guaranteed. Images do a pretty good job of representing the item.