PM Merelloy Mainspring for 10s Hamilton 6021 / 717102 - Alloy

PM Merelloy Mainspring for 10s Hamilton, Factory number 6021 / 20434 / 717102, alloy, new 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 in hard to find watch parts and all watch parts are unconditionally guaranteed. Images do a pretty good job of representing the item.