What is the correct size / air pressure for a NBA basketball ?
For size, the ball must be 29.5 inches in circumference (http://www.dickssportinggoods.com/product/index.jsp?productId=4152968)
As far as pressure, it must be between 7.5 and 8.5 pounds per square inch (http://www.basketball.com/nba/rules/rule1.shtml)
Another reference: http://www.livestrong.com/article/84284-basketball-official-size-weight/
Let me know if you have any questions,
MIT Graduate, United States Traveler, Information Finder