"Polypropylene is the hottest thing in thermal underwear on the market! This government issue 100% polypropylene is 1/16 in. thick with a fleece texture next to your skin. Our troops use these long johns with their extreme cold weather gear. Polypropylene is designed to wisk away moisture from your skin to keep you warm and dry. All new. Bottoms have a 1¼ elastic waistband, built in fly and snug 2 in. cuffs at ankles. Sizes XXL (32 in. inseam), XXXL. Shirt sold seperately."