 This product is designed to help protect your feet from the damaging effects of impact, shear and blistering common to participating in fitness regimens and workouts. Extra THOR•LON® provides a maximum fitness density padding to provde better durability, protection against shock, impact and shear forces. Lighweight padding in arch with added spandex provides extra support and stability during twisting and lateral movements. Heavier ball padding to reduce impact. 81% THORLON Acrylic, 15% Stretch Nylon, 4% Spandex |