[sphere and ash]

The 5x baseball, so called because it was 5% livelier, was an experimental baseball. It was used during spring training in 1970 and discontinued because of concerns over the safety of both players and fans. Cronin, whose stamp appears on the ball, referred to the 5x derisively as Bowie Kuhn's "little experiment," and said, "I've seen enough of it. It should be outlawed."

I own both American and National League 5x balls. The National League ball's stitches are one color, though lighter than typical. Red and blue stitches would let players and umpires identify the ball immediately--an important design element given potential safety concerns.