bamboo yarn(21s,32S 40S etc): 1,100% bamboo 2,50%bamboo and other 50% 4,polyester As per buyer`s requrement ... result, with 500W halogen light shone on the bamboo charcoal yarn for 10 minutes, the yarn emits far infrared rays for 87% ~ 92 ... , shirts, warm clothing, health care apparel, socks, towels, etc. 32S Bamboo yarn