Dunlop ATP Championship Regular Duty 24 Cans The Dunlop ATP Championship Regular Duty 24 Can case features tennis balls officially endorsed by the ATP World Tour. These tennis balls are ideal for the club and recreational level tennis players for use on clay and indoor courts. HD Pro Core and Fluoro Cloth technology combine to create a consistent feel that lasts match after match. 3 balls per can. Suitable for play on indoor and clay courts. Approved by the USTA and ITF.