The hummingbirds on this pair of silky soft Bamboo socks would be pleased to know that our fabric is approved by the FSC® for being sourced from responsibly managed forests. Accredited by the Forest Stewardship Council® for being sourced from responsibly managed forests Certified by OEKO-TEX® Standard 100 for zero harmful substances present Made using rayon from bamboo for a super-soft sock Seamless toe which limits irritation or chafing Blended with nylon for durability and spandex for flexibility Moisture wicking and great for sweaty feet Kind to sensitive skin 66% Rayon From Bamboo, 32% Nylon, 2% Spandex