12u is a continuation of the philosophy to fit the diamond to the physical potential of the players. The bases and pitching distances are scaled up slightly from  10u.

The transition diamond used in  12u permits infielders and outfielders to select their defensive positions in relationship to the anticipated speed of the ball when hit and thrown. Without this transition diamond,  12u players play their position disproportionately closer to the bases, infield and pitcher.

This diamond positions the infielders and outfielders in direct proportion to that assumed by Major League Baseball players and permits the younger players to play the game as it was designed to play.

Rules of play are adjusted slightly from 10u to bring players another step closer to all-out baseball.