Columbia Men's Baselayer Heavyweight Tight with Fly 98% Polyester /2% elastane Imported 85% polyester/15% elastane 85% polyester/15% elastane^Omni-Heat thermal reflective^Omni-Wick advanced evaporation^Machine wash cold gentle, do not bleach, tumble dry low, remove promptly, do not iron, donot use fabric softener, do not dry clean^