Card fronts feature a black-and-white head shot of a player within a diamond shape, showing a solid color behind; this is surrounded by four panels (usually yellow and white) separated by a white border by a thin red frame; at the upper left and bottom right are a red baseball graphic with a term denoting a game situation (Foul, Strike, Single, etc.). The lower left panel gives the player name and brief biographical data; along the lower right edge of the diamond is the card number and set total.
Card backs show a red generic baseball-themed graphic.
Like their counterparts the Blue-Backs of the same year, these cards were meant to be used to play a sort of baseball card game. These were generally sold two cards for a penny in a pack.
This was Topps's first baseball card issue, and - long story short - they were not successful, despite hopes that the company could take a bite out of rival Bowman's increasingly sizable share of the baseball card market. Not to worry, Topps executives would buckle down and produce the far superior 1952 card set, but in the meantime, collectors just didn't cotton to this half-hearted, generic release.
Note that the Red Backs are much more plentiful (and thus sell more cheaply) than the Blue Backs, due to the fact that a rather large hoard of them were found in the 1980's and disseminated into the hobby.
Prominent cards in this set include:
1 - Larry (Yogi) Berra
5 - Phil Rizzuto
22 - Bob Feller
30 - Warren Spahn
31 - Gil Hodges
36 - Gus Zernial (error)
38 - Ed (Duke) Snider
52 - Tommy Holmes (error)