The Wilson Jumbo US Open Tennis Ball 9 Inch size is a larger inflated version of the Wilson US Open tennis ball that bounces just like a basketball. The Wilson Jumbo US Open Tennis Ball measures 9 inches in diameter and is about the size of a basketball. It features real tennis ball felt all around also. This jumbo tennis ball is fun for kids or adults of all ages. It is also great as a toy to play with or just to display. The Wilson US Open Jumbo Tennis Ball is great to bring to tournaments for all those autographs!