BESTFIT Mainspring 510M for Buren 410, 470, FEF 350, 380, Gruen 545, Benrus R - Alloy

BESTFIT Mainspring 510M for Buren 410 & 470, Fleurier 350, 380, Gruen 545, Benrus "R" caliber movements and perhaps similar ébauche watches, white alloy, new in envelope. See images for precise characteristics. I likely have several of these so the one you get may vary slightly from the image. 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.