The Smartwool Men's NTS Midweight Pattern Crew can be worn as a base layer under jackets in winters but, of course, not limited to it as you may like to wear it on warmer days in springs and autumn. It has a unique flat-stitching on the seams, which not only looks great but also prevent chafing and scratching. The “pressure points" such as shoulders have been made thicker to make it easy for you when you are carrying a backpack. The snug fit is reinforced with an elastic round collar and wide bands at the wrists, so you won't look bulky or stuffed. The 100% Merino wool used feels warm and soft to touch.