Viking Platform Extra Duty Balls Yellow 6 Sleeves Platform Tennis Balls : Go with the player's choice. As the official ball of the APTA, the Viking Platform Extra Duty ball is a reliable option for pros and recreational players alike. The extra-duty advanced flocking process promotes longer wear and provides the perfect texture for maximum control and spin. Enjoy a soft feel and consistent bounce from the high-end rubber and glue compound. For players who want the best, select the Viking Platform Extra Duty Balls! Contains 6 sleeves, 2 balls per sleeve