It takes magnification and a bright halogen lamp to easily identify the source of the "MK" on this card an erased pencil marking in the upper-left corner of the reverse. While certainly present the mark about the most unobtrusive marking one would find on a card. Save for that this is a well-centered attractive Sport Kings card of Babe Ruth with honest wear throughout - corners edges and surface alike though none of the wear is overwhelmingly strong. The 1933 Goudey Sport Kings Ruth is one of five different mainstream Ruth cards inserted into gum packs by Goudey that year; clearly the most popular player in baseball and likely the most famous figure in America. The Sport Kings set is the hobby's most popular multi-sport issue with a wide variety of names that rank among the most popular of all-time in each respective sport. None however even approaches the popularity of Babe Ruth undoubtedly the key card in the set. The value of Ruth cards continues to skyrocket and popularity of the Sport Kings set continues to grow with the most presentable collector-grade examples fetching prices unheard of just a few years ago. A superb example of one of the most popular issues to feature the hobby's greatest and most widely-recognized name and face.