JB Field's Merino Wool Thermal Hiking Socks (2 Pairs) 64% merino wool Content: 64% Merino Wool, 30% Nylon, 4% Elastic, 2% LS Full thermal padding perfect for colder climates Preshrunk Wool : Merino Wool is the finest quality of easy care wool for exceptional warmth and softness. Wool features inherent qualities such as wrinkle resistance, colorfastness, shape recovery (resiliency), and is very breathable. Made in Canada