Bridgedale Womens Speed Trail Coolfusion Run Socks 55 % Nylon Polyamide, 22% Merino Wool, 21% Coolmax Polyester, 2% Lycra Elastane Lightweight Merino A great sock for trail or mountain running Merino wool for added comfort and softness Comes with a Free Helicase Sock Ring to keep the socks together in the wash