Gruen Factory Mainspring for Gruen caliber 480 - steel

Gruen Factory mainspring for calibers 480 movements, and quite likely others, steel, new in envelope. Yes, it says unbreakable mainspring and so you might conclude that it's an alloy mainspring, but it is not. I likely have several of the so the one you get may differ slightly from the images but they are all the same mainspring. 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.