BESTFIT Mainspring 510K for Buren 370, Benrus AL, MST 537 & Gruen - Alloy

BESTFIT Mainspring 510K for Buren caliber 370, Benrus "AL", Gruen 315, 355, 885 plus MST 357 and perhaps similar ébauche watches, white alloy. See images for precise mainspring specifications. I likely have several of these so the one you get may vary slightly from the image. See image for precise mainspring specifications. I specialize is 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.