Elgin Factory Mainspring for 5½ Ligne Grade 313 (FEF 6620) - Alloy

Elgin Factory Mainspring for 5½ ligne Grade 313 movement, Swiss (tongue) end, alloy, new in envelope. This Grade 313 (not to be confused with the much older 16s of the same grade) is a FEF caliber 6620 based Swiss ladies bracelet movement. See images for further details. I specialize in hard to find watch parts and all watch parts are unconditionally guaranteed. Images do a satisfactory job of representing the item