Skins Men's Bio Sport Compression Sleeves Nylon 76% / Spandex 24% Imported 76% Nylon, 24% Spandex 76% Nylon, 24% Spandex Engineered gradient compression delivers more oxygen-rich blood to your active muscles - so you can train harder, play longer and recover faster. Cold machine wash, gentle cycle, with like colors. Do not bleach, iron, or tumble dry.