Do you really know thyssenkrupp elevator S8 door contact switch?

Do you really know thyssenkrupp elevator S8 door contact switch?
We have a detail photo to show the different.
There have lots of S8 elevator door contact switchs on the market, how to differentitate?
1, For now there have three kinds of S8 elevator swtichs now.
2, A: original, we supply now;
   B: copye that made in China, not bad quality, 50-70% performance as original.
   C: copy that made in shangdong....very bad quality, 10-20% performance as original.
3, You can see the detail different on the photo as follows: