Cotton,Spandex.SOFTNESSCOMFORTLASTINGNESS- SIONCY COTTON NO SHOW SOCKS Made from high quality cotton/spandex which enhances durability, comfortability and also breathable.HEEL GRIP- Sioncy no show socks have Clear SILICONE grips at the heel. We add in this rubberized strip to help the socks stay on your feet well.VERSATILITY- Sioncy no show invisible thin socks include different solid color and packs, black white nude and grey socks and with combination of 1/3/6/9/12/15 pairs no show socks.SIZE-SIONCY NO SHOW SOCKS Fit for women shoes size US 5-10( fits for most ladies and teens).APPLICABLE- Ideal socks for athletic, casual or business conditions including dancing, doing gym,running,shopping,working or travelling, and other indoor & outdoor activities .