NIKE Women's Everyday Plus Lightweight Footies (3 Pairs) 57% Nylon/40% Polyester/3% Spandex (fabric content may vary slightly) Micro-nylon and spandex fabrics provide a soft feel Interior anti-slip silicone print on heel helps reduce slippage Ventilated mesh helps keep feet cool and dry Supportive arch band reduces bunching Small (4-6); Medium (6-10); Large (10-13)