Pro Penn Marathon - Tennis Ball 4 Pack Felt:Extra Duty mildew or rot while the

mildew or rot while the headband has been lock sewn with 4 rows of 32# white polyester thread and the side and bottom tapes double lock stitched with black polyester thread

Fabric: 91% Nylon/9% Lycra

made using nylon

this string has a surprising amount of touch and feel

The customizable vibraton dampener used by Rafael Nadal

Pro Penn Marathon - Tennis Ball 4 Pack Felt:Extra Duty mildew or rot while thePro 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