Sandsteel Mainspring #827 for Longines caliber 17.25 - Steel

Sandsteel steel mainspring #827 for Longines caliber 17.25 (17/25) plus likely other movements as well. 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.