The J.B. Field's 40 Below is one of the warmest thermal socks we make and contains an astonishing 85% wool! It was designed for people who require a sock that can keep their feet dry and warm in the most extreme conditions. We recommend wearing a liner sock to help wick away moisture because it will keep your feet smelling fresher, warmer and blister free!

• Medium (Women's 5-9 Shoe / Men's 4-8 Shoe)
• Large (Men's 8-12 Shoe / Women's 9 -13 Shoe)
• X-Large (Men's 13-15 Shoe)

Features:

• Content: 85% PreShrunk Wool & 15% Nylon
• Pre-Shrunk Wool - We only use the finest quality of easy care wool in our socks because it is such a versatile fiber. Not only is wool breathable but it is great at helping regulate body temperature by keeping your feet dry and wicking away moisture helping prevent blisters and control odor.
• X-Hi Cushion - Full terry cushion for extra warmth and protection.