Swartchild Black Shield SUPER Mainspring for Gruen 405, Wasa 110 - Alloy

Swartchild Black Shield SUPER Mainspring for Gruen 405, Wasa 110 caliber movements as well as similar ébauche watches (there are several related Gruen calibers), white alloy, new in envelope. I likely have several of these so the one you get may differ slightly from the images. 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.