2.375x2.875".  The issue consisted of 239 cards, with a 240th entry - the remarkably scarce Napoleon Lajoie #106 - produced in 1934 in response to consumer outcry and mailed to fans only upon request.

Herbert Jefferis Pennock (February 10, 1894 - January 30, 1948) was an American professional baseball pitcher and front-office executive. He played in Major League Baseball from 1912 through 1933, and is best known for his time spent with the star-studded New York Yankee teams of the mid to late 1920s and early 1930s. Pennock was a 6 time World Series champion and was inducted into the National Baseball Hall of Fame in 1948.