Penn 521190CAN ATP World Tour Reg Duty Tennis Ball Can NA/P Imported Penn ATP World Tour tennis balls are the #1 choice of ATP players and the official ball of the ATP World Tour, used in 4 out of the 5 largest tournaments in North America. These premium tennis balls are covered with Penns exclusive LongPlay felt for extended wear, and feature our Smart Optik high visibility felt treatment for maximum brightness... Penn Tennis Balls | Atp | Regular Duty Size - (See Description) | Color - (See Description) Authorized Penn Dealer. All racquets are strung and ready for the courts! SEE SELLER DETAILS FOR RETURN POLICY.