Nylon 90% Nylon/10% Lycra - Microfiber Size Small/Medium (4'11"-5'5" / 90lbs-135lbs); Size Medium/Large (5'5"-5'11" / 135lbs-170lbs) 80 Denier, medium thickness, solid opaque color Full-footed, no cotton gusset. No reinforced Toes. Incredibly soft, stretchy and durable.