Hamilton Dynavar 16s Mainspring No. 35434 / 717041 - Alloy

Hamilton Dynavar Factory Mainspring for 16s Movements, specifically the 950B and the 992B, Factory No. 35434 (new number 717041), alloy, in envelope. See images for further details. I likely have several of these so the one you get may differ slightly from the images. I specialize is hard to find watch parts and all watch parts are unconditionally guaranteed. Images do an adequate job of representing the item.