Elgin DuraPower Factory Mainspring for 13/0s grades 750-751-752 - Alloy

Elgin Factory DuraPower Mainspring for 13/0s grade 750 thru 752 movements, alloy, new in sealed envelope. Available in a couple of different strengths, which you can choose from. See image for specifications. 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