These have been appearing on the back of all UD's sports card since the 2006-07 NBA and NHL season. I have no idea what purpose they serve. They do not appear on the non-sports cards they produce, at least not the Marvel Cinematic Universe cards I have in my collection.
I've cropped down an example from an NBA and NHL card to show. The VM7VG and K3EWX is what I am referring to.
So anyone know what these are there for?
VERY slow trading due to health problems. Not transferrable so safe to trade with, just moving is painful and can't always access the cards.
Cardboard History My COMC
New Collection Website: Cardboard History Gallery (Still under construction)
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