HR Mainspring #331 for Brac caliber 40 movements - Steel

HR Mainspring No. 331 for Brac caliber 40 & 180 movements plus perhaps other similar sized watches, steel, new in dirty envelope. See image for precise mainspring specifications. 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.