Elgin DuraPower Factory Mainspring for 0s & 3/0s 2097 / 6095 - Alloy

Elgin Factory DuraPower Mainspring for 0s & 3/0s movements, Factory No. 2097 / 6095, new in envelope. These are available in a couple of strengths which you should be able to select from the drop-down list. See images for precise specifications. I likely have several of these so the one you get may differ slightly from the images, with some of the envelopes quite likely being open. I specialize in hard to find watch parts and all watch parts are unconditionally guaranteed. Images do a pretty good job of representing the item.