PM Mainspring for Bulova caliber 10AK movements - Steel

PM ONYX steel mainspring for Bulova caliber 10AK movements, new in decapitated envelope. See images for precise mainspring specifications. Someone cut off the top of each envelope, presumably so it would fit into their parts system. 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.