Made of high-filament Polyester enhanced by slight brushing to provide softness and warmth, the Ski-Doo ladies' thermal base layer bottoms are the base layer you want against your skin to provide moisture wicking properties and insulation during winter's coldest days. Made of 95% Polyester and 5% Spandex. Features Made of high-filament Polyester enhanced by slight brushing to provide softness and warmth. Mesh paneled under arms for better ventilation and accelerated drying.