The Smartwool Men's Merino 150 Boxer Brief is comprised of a lightweight, core spun 150 merino wool that keeps you comfortable and dry in all conditions. With a wide waistband to maximize comfort and a fully functional fly, this boxer brief caters to your every need. Best used for Higher output activities in warmer weather conditions. Features of the Smartwool Men's Merino 150 Boxer Brief Lightest weight Merino jersey fabric Uses a nylon core to increase durability while keeping Merino wool next to skin Fully functional fly Wide elastic waistband (40 mm) designed for ultimate comfort; keeps Merino next to skin Flatlock seam construction designed to eliminate chafing