A baseball is a ball used in the sport of the same name. The ball consists of a rubber or cork center wrapped in yarn and covered with white natural horsehide or cowhide, or a synthetic composite leather. A regulation baseball is 9 to 9.25 inches (229 to 235 mm) in circumference i.e. 2.86 to 2.94 inches (73 to 75 mm) in diameter, with a weight of 5 to 5.25 ounces (0.142 to 0.149 kg).
