Elgin Factory Mainspring for 13/0s Grade 747 - Alloy

Elgin Factory Mainspring for 13/0s Grade 747 movements, alloy, new in sealed envelope. The grade 747 is an AS 1156 based movement and thus this mainspring may also work for a handful of other AS calibers. I likely have several of these so the actual one you receive 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