BESTFIT Mainspring 512E for Gruen 915 - 917, Benrus BN, MST 323, 422, OSCO 70 - Alloy

BESTFIT Mainspring 512E suitable for Gruen caliber 915, 916, 917, BIDL caliber 934, OSCO caliber 70, Benrus BN and MST caliber 323, 422, plus perhaps many other similar ébauche watches, white alloy. See image for precise characteristics. I likely have several of these so the one you get may differ slightly from the images. 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.