PM Mainspring #588 for Landeron caliber 39 Chronograph - Steel

PM steel mainspring No. 588 for Landeron 14½ ligne caliber 39 chronograph movements and I'm pretty sure some other Landeron calibers as well, 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.