Can you tell the difference between a 1966 Topps NHL Checklist PSA 6 vs PSA 4 ??
 

Both cards came back with no qualifiers
Take a guess which one is the 4 and which one is the 6
Russ

Very tough question because they look almost the same in the pictures. So, wild guess: One on the right because of top left corner. As I say, a wild guess.

I have been burned before because I didn't pay attention to the back of the card. Remember they grade both sides of the card. If the back is off center they may knock it down a couple of grades because you sent it without qualifiers. Maybe this helps.