BOREL Mainspring 4017-M for Bulova 6AK, 6BA, 6BC - Alloy

BOREL Mainspring 4017-M for Bulova caliber 6AK, 6BA, 6BC,  plus perhaps other similar ébauche watches, white alloy, new in 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.