Alloy Mainspring for Gruen 179, Bulova 9AN, 9AT

Unmarked Maker Swiss Mainspring for Gruen caliber 179 & Bulova caliber 9AN, 9AT movements, plus perhaps similar movements, GR Ref. 2918, white alloy, new in tiny 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 an adequate job of representing the item.