Marco Mainspring #3136 for Derby caliber 67 - Steel

Marco Mainspring No. 3136 for Derby 67 caliber movements, and perhaps other similar ébauche watches, steel, new in envelope. See images for precise mainspring specifications. 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 so I usually have whatever you might need and all watch parts are unconditionally guaranteed. Images do an adequate job of representing the item.