Elgin DuraPower Factory Mainspring for 26/0s No. 6101 - Alloy

Elgin Factory DuraPower Mainspring for 26/0s movements, Factory # 6101-.0031, alloy, new in envelope. See image for precise specifications. These were available in different strengths and if I have any they'll likely be shown as an option you an pick, otherwise you get the default -.0031. I specialize in hard to find watch parts and all watch parts are guaranteed. Images do a pretty good job of representing the item.