In conjunction with The Sporting News, Megacards issued various prototype cards to preview their soon to be released regular issue sets. All the cards were standard size. The 1991 Conlon prototypes from the first series were not marked as prototypes, and neither did they have the Major League Baseball logo and the Curtis Management logo on their backs. Their numbering was identical with the regular issue cards, with the exception of Dean (number 3 in the regular issue). The production run was reported to be very limited for these first series cards. The 1991 Conlon Color Babe Ruth prototype has the word "prototype" on its reverse. The 50,000 color Ruth prototype cards produced were distributed to collectors and dealers at the 12th National Sports Collectors Convention in Anaheim in July, 1991. Moreover, five prototypes for the second series (1992 Conlon Collection) were distributed at the same time. The production run was announced to be 20,000 for each card, with the exception of Joe Jackson (67,000). All these cards are marked "prototype" on their backs, and with the exception of the Mathewson card, also bear different card numbers from the regular issues. In general, some subtle differences in photos are found with some of the prototype cards. The second series prototypes show a 1992 copyright on the card back. The Cobb and Jackson cards have a computer color-enhanced photo with white and dark blue borders, while the other cards have black and white photos with white and black borders.