Marco Mainspring #2738 for A. Michel 270, 640, Font 274, 9444, Gruen 485, 487 - Steel

Marco Mainspring No. 2738 for Aurore 1, A. Michel 270, 640, Font 274, 9444, Gruen 485, 487, Bulova 6M, 6AO, 9P caliber movements and perhaps many others, 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 a pretty good job of representing the item.