Joe Louis' 1948 Leaf Knock-Out Bubble Gum card (#48) is among the most significant boxing cards ever produced — an artifact from the immediate postwar era that captures the "Brown Bomber" at the twilight of his unparalleled reign as World Heavyweight Champion. The Leaf set was one of the first nationally distributed boxing card issues, and Louis' card presents him in his iconic boxing stance with the bold red nameplate below. The reverse confirms his record of 61 wins, 1 loss, with 52 knockouts and 26 successful title defenses — numbers that stand as the all-time standard for championship defenses.

Graded PSA EX 5, this example shows honest wear appropriate to its nearly 80 years of age, including softened corners and light surface toning, while the image remains vivid and the colors bold. The 1948 Leaf set is the benchmark pre-war boxing card issue, and Louis' card is its centerpiece. Any serious combat sports collection or vintage card collection is incomplete without it.