A lightweight tee that performs and protects, featuring the most advanced active cooling technology in the industry with built-in UPF 50 — welcome to the Columbia Women’s Zero Ice Cirro-Cool Short Sleeve Shirt. Designed for an active fit and a flattering look with all-day comfort, this shirt includes a sweat and touch activated super cooling, along with our advanced UVA/UVB sun protection fabric. This comfort stretch polyester material is designed to move with you while wicking perspiration away. This women’s t-shirt comes in multiple colors and sizes. Active 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.