Longines Factory Mainspring for caliber 4.LL - Alloy

Longines Factory Mainspring caliber 4.LL (4LL) plus perhaps similar ébauche watches, alloy, new in package. The wonderful thing about factory mainsprings is they always fit! 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.