The back of the cards are always my favorite to look at. For some reason it always brings back to those old Fleer Ultra X-Men cards I collected as a kid. (Images at bottom of the post, provided by various websites)
The front shows the /10 numbering
Here are some of the old Fleer Ultra Marvel cards I loved as a kid. I sold my Marvel cards as part of my comic book liquidation in 2012 so all these images were from eBay.