Merrell Women's Siren Sport Sock, Raspberry, X-Large 50% Merino Wool, 28% Nylon, 20% Nano-Glide, 2% Lycra Made in US Cudhionrf heel and toe area Lightweight running sock Nano-Glide technology for friction-free comfort Arch band support to fight fatigue Reinforced footed for durability Cushion for heel and toe area