Tennis Number 1s
Wilson tennis balls 3 and 4?
What is the difference between Wilson (and Penn / other tennis ball made for that matter) 1s, 2s, 3s, 4s and? (The number under the brand name) Is it a size, durability, or something else?
The only purpose for which figures to help on the balls to distinguish those who belong to the balls. If you play in a yard next to other people, you know which ball is yours because of the numbers. This is really the only purpose.
