The ball is round, made of leather or other suitable material. The most classic football style ball circumference, not more than 70 centimeters (28 inches), not less than 68 cm (27 inches). The weight of the ball, at the start of the game, not more than 450 grams (16 ounces), not less than 410 grams (14 ounces). Ball pressure at sea level is 0.6 to 1.1 atmospheric pressure (per square centimeter of 600 grams to 1100 grams = 8.5 pounds per square inch to 15.6 pounds). Replacement of substandard ball, if in the game, the ball broken or substandard: stop the game. Replace the standard ball, where the ball is broken, the ball starts again.
If the ball is in the goal area, the ball is dropped on the goal line in parallel to the goal line.
If it is not in the game, such as midfield kick-off, goal kick, corner kick, free kick, penalty kick or throw the ball when you enter, broken or substandard: in accordance with the rules of the re start.
Competition time, without the consent of the referee, the ball can not be replaced.