Icebreaker Men's Bodyfit 150 Ultralite Short Sleeve Atlas T-Shirt 100% Merino Wool Imported A slim fitting base layer that is so comfortable you'll barely realize you have it on Underarm gussets and flatlock stitching maximize freedom of movement and eliminate chafing, while the athletic design and sizzling colors make the SS Atlas a joy to wear Non itchy, Fits close to the body, Flatlock stitching to eliminate friction from internal seams Flatlock side gusset and seamless underarm to reduce chafing