Marco Mainspring #3228 for Bulova 4AM, 6EA, ETA 746, Recta M, MV, 108, 109 - Steel

Marco Mainspring #3228 for Bulova 4AM, 6EA, ETA 746, Recta M, MV, 108, 109, Benrus BU caliber movements and perhaps others, steel, new in envelope. See images for precise mainspring specifications. 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.