Bestfit Balance Staff Refill for Kurth caliber 248 movements - New

One Bestfit Refill Series 8C3 Balance Staff #106 for Kurth caliber 248 movements and perhaps others as well, new in open envelope. Should be equivalent to a System 200 #441. See images for further details. These originally came packaged as 1/4 doz but there is only one in the envelope.  I specialize in hard to find parts so I'll usually have whatever you might need and all watch parts are unconditionally guaranteed. Images do an adequate job of representing the item.