Under Armour Women's Base 4.0 Leggings, Black 100% Polyester Imported UA Base 4.0: Mega-grid thermal fleece for the ultimate warmth in the brutal cold Thermal grid fabric traps heat in tiny pockets for long-lasting protection Quick-dry construction wicks moisture to keep you drier, lighter & more comfortable 4-way stretch construction moves better in every direction Anti-odor technology prevents the growth of odor-causing microbes