 This product is designed to help protect your feet from the damaging effects of impact, shear and blistering common to running/jogging. Extra THOR•LON® provides a maximum running density padding to provide better durability, protection against shock, impact and shear forces. THOR•LON® top with added spandex provides protection and better fit Lightweight padding in arch for better fit and arch support. Content: 86% THORLON Acrylic, 13% Stretch Nylon, 1% Spandex |