Pro Penn Marathon Extra Duty Butterfly Adjustable entry and release tension

Adjustable entry and release tension settings

0 is a high performing racing Jammer

available for young swimmers

We recommend you protect the rubber surface with rubber protective film after a match or practice

durability and visibility

Pro Penn Marathon Extra Duty Butterfly Adjustable entry and release tensionPro Penn Marathon is Penns longest lasting tennis ball featuring exclusive Encore Technology for a 22% longer lasting core and high tenacity LongPlay Felt for extended play . Pro Penn Marathon is the official ball of PTR because of its guaranteed longevity, durability and visibility. Pro Penn Marathon is available in Extra Duty Felt (for hard courts), Regular Duty Felt (for soft courts) and Extra Duty High Altitude (for higher altitudes). Penns