Work up a sweat without skimping on comfort with Smartwool's Men's Active Short Sleeve. Crafted with the odor resistance, moisture management, and temperature regulation properties of Merino with the durability of recycled polyester. The relaxed fit means there's no additional bulk, with offset shoulder and side seams designed to help increase comfort and minimize chafing, no matter how you move. This short sleeve is complete with reflective elements.