Ideal for young players learning how to pitch, the Champion Sports Weighted Baseball Set allows each pitcher the ability to gradually increase arm strength through a four to 12 ounce range. Each set contains 1 each: 4 oz, 5 oz, 6 oz, 7 oz, 8 oz., 9 oz., 10 oz., 11 oz. & 12 oz. baseballs. (TK)