National White Alloy Mainspring for Waltham 6¾ Ligne No. 2244 / 2261

National mainspring for Waltham for 6¾ Ligne Model 670, Factory Nos 2244 / 2261, alloy. See image for precise characteristics. I specialize in hard to find watch parts so I usually have whatever you might need and all watch parts are unconditionally guaranteed. See image for further details. Images do a pretty good job of representing the item.