Developed to keep you at the optimal temperature throughout any workout in fair , cold and windy conditions. Be Active Extreme Windstopper® is made of a thin, lightweight and elastic micro polyester fabric and Gore Windstopper® panels. Air-channeled polyester expels excess heat away from the body while filament yarns transport the moisture. The Windstopper® panels are placed in exposed areas, providing wind protection and freedom of movement simultaneously.