The Mens Terramar Merino Wool Crew is a soft medium weight insulator. Made with 100% super soft Merino Wool, the Terramar Crew is breathable, natural, and itch-free. The machine-washable Merino Wool Crew keeps you warm in cold weather; cool when overheated; and has a 50+ UPF Rating. Other features include set-in sleeves, chafe-free seams, and a drop contoured back hem. The Mens Terramar Merino Wool Crew keeps you warm even when wet.