It is equivalent to the top military bags currently used in europe. This bag is waterproof, but it also has a state-of-the-art draft tube that helps prevent heat loss. Its centered zipper makes getting in and out easier and keeps you more comfortable while sleeping. Outer fabric: 100% polyamide. Inner lining: 100% polyamide. Sizes: m, l, xl. Outer dimensions (cm): 215/85/57 (m), 230/87/60 (l). Weight (g): 1.850 (m), 2.000 (l). Pack size compressed (cm): 25×30 (m), 25×32 (l). Good to -30 degrees fahrenheit. This item is made of polyester and polyamide.