Pro Penn Marathon is the official ball of PTR because of its guaranteed longevity, durability and visibility. Penn's longest lasting tennis ball, the Pro Penn Marathon is the #1 choice among USPTA Teaching Professionals. These feature Penn's Encore technology for a 22% longer lasting core and high tenacity and LongPlay felt for better durability.
Optik felt keeps visibility at a maximum. The Extra Duty felt is for hard courts and is a High Altitude ball for use over 3500 ft. The ball, along with the racket, is arguably the most important piece of tennis equipment.
The tennis ball must lie within the specifications laid down in the Rules of Tennis while providing consistent playing properties and being sufficiently durable to withstand repeated high-speed impacts with the racket and surface.,Pro Penn Marathon is the official ball of PTR because of its guaranteed longevity, durability and