The National Collegiate Athletic Association (NCAA) rules stipulate color, weight, size and number for the balls to be used in the sport of water polo. In addition, the ball must be waterproof and free of strappings and slippery coverings.
SECTION 1. The ball shall be round, predominantly yellow or gold in color, and have the traditional 18 panels. It shall have an air chamber with a self-closing valve. It shall be waterproof, without external strappings or any covering of grease or similar substance. The colored panels must be as manufactured (not hand-painted).
SECTION 2. The weight of the ball shall be not less than 400 grams and not more than 450 grams.
SECTION 3. For games played by men, the circumference of the ball shall be not less than 0.68 meters and not more than 0.71 meters, and its pressure shall be 90 to 97 kilopascals (13 to 14 pounds per square inch atmospheric).
SECTION 4. For games played by women, the circumference of the ball shall be not less than 0.65 meters and not more than 0.67 meters, and its pressure shall be 83 to 90 kilopascals (12 to 13 pounds per square inch atmospheric).
SECTION 5. At least five game-quality balls must be available for all games. One ball shall be with the referee and two at each bench, or with the goal judges, as determined by the tournament committee. If there are not ball boys/girls, the coach must have a team member from the bench immediately retrieve the ball if it goes out of bounds over the end line. If the coach does not do this, the referee shall warn the coach and, at the next occurrence, give the coach a yellow card. A player in the field of play may retrieve the ball only if the player does not have to leave the field of play or with the permission of the referee. If the referee did not give the player permission to leave the field of play, the referee will exclude the player for 20 seconds (see Rule 21-4).
NCAA Water Polo Rules- http://static.psbin.com/9/1/beyyi0ufof5ihc/NCAA_Rules_2014_16.pdf.pdf
Photo – www.usawaterpolo.org/genrel/043013aaa.html