I've searched & asked for the OEM convex glass without any success. It looks like they've offered it for a very short while and then pulled it off from the US market. In Europe, it's way expensive.
As a side note, I'd never put a Walmart blind spot mirror on my X6. I'd rather turn my head & look for the lane rather than use a cheap looking stick on mirror on a great looking CUV like this..
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