Laws of Cricket 1980 Code - Law 5
1. Weight and Size The ball, when new, shall weigh not less than 5-1/2 ounces/155g, nor more than 5-3/4 ounces/163g; and shall measure not less than 8-13/16 inches/22.4cm, nor more than 9 inches/22.9cm in circumference.
2. Approval of Balls All balls used in matches shall be approved by the umpires and captains before the start of the match.
3. New Ball Subject to agreement to the contrary, having been made before the toss, either captain may demand a new ball at the start of each innings.
4. New Ball in Match of Three or more Days Duration In a match of three or more days duration, the captain of the fielding side may demand a new ball after the prescribed number of overs has been bowled with the old one. The Governing Body for cricket in the country concerned shall decide the number of overs applicable in that country which shall be not less than 75 six-ball overs (55 eight-ball overs).
5. Ball Lost or Becoming Unfit for Play
In the event of a ball during play being lost or, in the opinion of the umpires, becoming unfit for play, the umpires shall allow it to be replaced by one that in their opinion has had a similar amount of wear. If a ball is to be replaced, the Umpires shall inform the batsmen.
Notes
1. Specifications
The specifications, as described in 1. above shall apply to top-grade balls only. The following degrees of tolerance will be acceptable for other grades of ball.
1. Men's Grades 2-4
Weight: 5-5/16 ounces/150g to 5-13/16 ounces/165g
Size: 8-11/16 inches/22.0cm to 9-1/16 inches/23.0cm
2. Women's
Weight: 4-15/16 ounces/140g to 5-5/16 ounces/150g
Size: 8-1/4 inches/21.0cm to 8-7/8 inches/22.5cm
3. Junior
Weight: 4-5/16 ounces/133g to 5-1/16 ounces/143g
Size: 8-1/16 inches/20.5cm to 8-11/16 inches/22.0cm
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