Cas-Ker Mainspring JA113 for 0s & 3/0s Elgin Factory No. 6094 - Alloy

Cas-Ker Mainspring MS-JA113 for 0s & 3/0s Elgin, Factory No. 6094, Probably made by Bestfit, new in 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 in hard to find watch parts and all watch parts are unconditionally guaranteed. Images do a pretty good job of representing the item.