Sold in packages of two for a penny, the Topps "Red Back" set was a 52-card set, intended for game play, each card featured a baseball-themed design printed in red ink.  The Red Back set is considered more plentiful than the 52-card "Blue Back"  set (which featured, you guessed it, blue-backed cards), partially because the cards were known to have been sold as a complete set, and partially due to a large number of unopened boxes in the 1980s.

Presented here is a collector-grade complete set, numbering 52 cards (the set includes the tougher "Chicago bio" card of Gus Zernial but the easier "Hartford bio" card of Tommy Holmes).  A condition breakdown of the set would be 4% EX, 10% VG/EX, 18% VG, 33% GOOD, 25% FAIR, and 10% POOR, the primary condition flaw relating to creasing, an obvious result of the handling that comes with playing the game.  Key cards are as follows: #1 Berra (P), #5 Rizzuto (G), #8 Wynn (G), #15 Kiner (VG/EX), #22 Feller (G), #30 Spahn (F), #31 Hodges (VG), #38 Snider (VG), #50 Irvin (VG).  52 cards total.