*Think of this extra-tall Outlast® sock as a climate-control system for your rubber boots *Outlast® fiber balances foot temperature to prevent feeling too hot or too cold *Fully cushioned design *Seamless toe closure *44% Outlast® acrylic, 19% olefin, 19% wool, 17% stretch nylon, 1% spandex *Made in USA *One pair per package *Size M fits Women's shoe sizes 6 to 10 and Men's shoe sizes 5 to 9-1/2 *Size L fits Women's shoe sizes 10 to 13 and Men's shoe sizes 9 to 12 *Size XL fits Men's shoe sizes 12 to 15