Marco Mainspring #3227 for AS 1323, Bulova 9AS, 10BRC, Kurth 257, 258, Tavannes 404 - Steel

Marco Mainspring No. 3227 for AS 1323, Bulova 9AS, 10BRC, Kurth 257, MST 237, Tavannes 404, Wittnauer 9AR caliber movements and perhaps even others as well, steel, new in dirty envelope. See images for precise mainspring specifications. I likely have several of these so the one yo get may differ slightly from the images. I specialize is 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.