1. Size for Circumference of circle
Due to the differ in size for circumference of circle, it can't be fit on well both insert on and the case in. Even it can be fit on, the bezel can't be rotated properly or hard to be rotated. Also it may be caused by no play in bezel.
2. Thickness of the bezel
There is different from the thickness it causes above issue as well.
If glue on bezel for fitting insert on, genuine one is easy to get rid of glue with alcohol but FAKE one is not, it's very hard to get rid of it.
He wanted me to put his bezel on here and ask if it is genuine or not. According to his policy, all of the money could be refund if bezel is not original. I know he has sold several nice items here before but this bezel isn't the one unfortunately...
So he has to admit this fact even he doesn't notice that it is fake.