RN Mainspring No. 722 for Unitas caliber 180 -186 movements - steel

RN mainspring No. 722 for Unitas 180 - 186 caliber movements, steel, new in envelope. See images for 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.