20107 is our thickest and warmest wool sock. The wool provides warmth and insulates in cold weather, as well as keeping your feet dry on sweatier days. The strong wool terry loops on the inside of the sock create a warming and insulating layer of air between the foot and the shoe. The sock is reinforced with polyamide for maximum strength and durability. Öko-Tex certified. Washing instructions: 40°C, should not be tumble dried. Material: 68% Wool, 18% Acrylic, 12% Polyamide, 2% Elastane.