Keep your temp down on the hike up with this technical tee, made with comfort stretch fabric that moves with you – utilizing the most advanced active cooling technology in the industry. Designed for an active fit and a flattering look with all-day comfort, this shirt's sweat-activated super cooling polyester material is designed to move with you while wicking perspiration away. A Columbia women's shirt that comes in multiple colors and sizes. Extended sizing available. Active and Regular Fit. To ensure the size you choose is just right, please refer to our sizing chart. To find your waist measurement, measure around your natural waistline.