Nivaflex Unbreakable Mainspring N6387 for Lanco 1036, 1136, MST 371, 372, Oris 450, 451, 452, 453 - Alloy

Nivaflex Unbreakable Mainspring N 6387 for Langendorf 1036, 1136, MST 371, 372, Oris 450, 451, 452, 453, Reconvillier 120 caliber movements plus perhaps other similar ébauche movements as well, alloy, new in envelope. See images for all supported calibers and 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.