88% Rayon from Bamboo, 10% Nylon, 2% Spandex Imported Machine wash cold, Tumble dry low RAYON from Bamboo Fiber, 3-Pair Pack Crew. BAMBOO Naturally Anti-Microbial and Anti-Fungi. Moisture-Wicking And Odor-Fighting. JACQUARD warm Pattern, Soft and Cozy. Treated Wash. Perfect for everyday wear. MEDIUM Thickness, Spandex added for comfort. IDEAL for Outdoor wear. NON-BINDING Top, Great Hand Feeling.