NEWALL Mainspring #1737N for Benrus CA, AS 1111, 1179, Unitas 510, 520 - Alloy

NEWALL Mainspring #1737N for AS 1111, 1179, FHF 60, 601, Benrus CA, Unitas 510, 520 caliber movements plus perhaps other similar ébauche watches, alloy, 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.