I often buy the holder but in this case I bought the card. The MK is a faint, half-inch ink mark on a deep black background on the back--in other words, only visible in certain light and at an angle. The card could have gotten a 5, and it's well-centered. I wonder if there's more than one or two better looking Duffys out there....
http://www.net54baseball.com/attachm...1&d=1455338320