HR Mainspring No. 541 for AS 340, 689 & Bulova 10AL - Steel

HR mainspring No. 541 for AS 340, 689 & Bulova 10 AL movements plus perhaps others, steel, new in envelope. See images for precise mainspring specifications. 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.