BESTFIT stem for A. Michel caliber 520, 560

One BESTFIT stem for A. Michel caliber 520, 560 movements and possible variants, new in open envelope. This is Position Number 16 from the Bestfit #200 Stem System. Yes, the package says 1/4 doz but there is only one in the envelope.  I specialize is hard to find watch parts so I usually have whatever you might need, all watch parts are unconditionally guaranteed and offers are welcome. Images do an adequate job of representing the item.