Dynaflex Unbreakable Mainspring for Bulova 4AC - Alloy

Dynaflex Unbreakable mainspring for Bulova caliber 4AC plus perhaps other similar ébauche movements as well, alloy, new in envelope. See images for further data and 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.