Duofold Men's Expedition Weight Two-Layer Thermal Tagless Crew 100% Spandex Imported base-layer-underwear closure Machine wash cold with like colors. use only non-chlorine bleach when needed. no fabric softener. tumble dry low. do not iron. 96% Polyester, 4% Spandex bi-ply fabric Duofold's Expedition Weight was developed specifically for the U.S. Special Forces for warmth in extremely cold weather 360 stretch for maximum flexibility and optimum fit, excellent moisture management, quick drying and odor resistant TAGLESS for added comfort and flatlock seams to help avoid irritation Imported