Thermal Knit Bottoms - Natural color beige aka ekru, thermal men's underwear long john style thermal underwear for men. 55% Cotton/45% Poly blend. Stay warm in cool weather. Ultra force toasty warmth for cold weather activities and jobs. Double fabric fly and crotch. (Tops are separate) Small through 3XL (additional cost for 2x 3x, Small 30-32", Medium 34"-36", large 38-40, XL 42-44, 2XL 46-48, 3XL 50-52 sizing is per manufacturer and has not been tested.