Russell Men's Performance Active Baselayer Thermal Pant / Bottom 95% Polyester 5% Spandex 4-way stretch mobility & flexibility. Built-in odor protection. DRI-POWER 360 wicks sweat to keep you comfortable and dry. Moves with you and retains shape for comfort and support. THERMIC-POWER creates a barrier that helps keep heat in. 95% polyester / 5% spandex.