Smartwool Men's Active Ultralite Long Sleeve Active shirt Tshirt size medium New with tags in Marmelade. The athletic fit of our Men's Active Ultralite Long Sleeve complements the movements of your body. With comfort features like offset shoulder and side seams to help minimize chafing, this very light and soft tee is made with a blend of ZQ-certified Merino wool and TENCEL™ Lyocell fibers, a performance fabric that helps you feel cool even as your activity intensifies. Plus, it's designed with reflective elements for low-light conditions, so this tee is great as a standalone for early-evening runs or as a baselayer for your next cool-weather adventure.