N.B.MS Mainspring for Elgin 10/0s movements No. 1957 - Alloy

N.B.MS Mainspring for Elgin 10/0s movements, Factory No. 1957, alloy, new in envelope. See images for further details. I specialize in hard to find watch parts so I usually have whatever you might need and all watch parts are unconditionally guaranteed. Images do an adequate job of representing the item.