HR Mainspring No. 189 for Gruen 161, 1617 movements

HR No. 189 steel mainspring for Gruen caliber 161, 290, 1617 movements, and quite likely others, steel, new in envelope. See images for 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.