HR Mainspring SA701 for 18s Waltham Factory No. 2203 - Alloy

HR Mainspring SA701 for 18s Waltham Model 1877-1979, Factory No. 2203, T-end, alloy, new in dirty envelope. See images for precise mainspring specifications. I likely have several of these so the one you get may differ slight 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.