It will feel like you're running through the clouds in the Patagonia Men's Capilene Air Crew. This long sleeve offers amazing warmth and comfort range. An airy blend of soft, stretchy fabric wicks moisture, resists odor and dries in a flash. All of the virgin wool Patagonia sources is certified to the Responsible Wool Standard (RWS) from farm to fiber to help ensure protection both for the animals that supply it and the land they graze.