1、The ball for the competition is a rubber ball with uniform surface and yellow or white color. The diameter of the ball is 6.35-6.77 cm and the weight is 56.0-59.4 grams.

2、When the ball freely falls down from 2.54 m to hard ground, the rebound height shall be between 135-145 cm.

3、The internal pressure of the ball for competition shall be 4.6 - 5.2 kg / 2.54 cm².

4、When the competition proceeds at the altitude of above 500 meters, the ball with rebound height of 121.92-135 cm can be selected, and other specifications are the same as above.