BambooMN - 3 Pairs of Women's Rayon Bamboo Fiber No Show Invisible Sock Liner 10% polyester Content: 85% Rayon from bamboo, 10% Polyester, 5% Elastic Two Sizes: Size M/L is 21cm long and fits women's shoe size 4-10; Size XL is 23 cm long and fits women's shoe size 10-13. Rayon - Natural, Renewable, Biodegradable, Anti-microbial / Natural Deodorizer. Bamboo fibers also gives these bamboo socks a smooth, silky feeling. These bamboo socks are more breathable than cotton, fast drying and moisture-wicking. Great for sweaty feet. Non-Slip silicone grips around heels prevent these womens peds from slipping off while walking Machine Wash and Dry, Do Not Bleach, Do Not Iron, Do Not Use Softener, Tumble Dry Normal, Dry Clean and Solvent Except Trichloroethylene