Go farther, stay comfortable. Designed for long days hiking in extreme terrain and conditions. Easy on the foot, but tough on cold, sweat, heat, moisture. Slightly lighter weight than our Trekker socks, but still "Seriously warm-Surprisingly soft", our newest extreme sock, that will keep your feet warm and dry all winter long. Ultra-soft bison fiber that has been properly processed, no prickly itch from these socks. Thicker and more cushioning than our Pro-gear socks.
This sock has a terry loop padded footbed, and lighter ribbed construction all the way up the calf with just enough spandex to hold it above your 10" boot top...but not enough to cut down circulation. Nylon over-plaited in the toe and way up past the heel for long smooth wear.
Superior breathability, temperature regulation, and natural odor resistance!!
Sock Sizing
Socks should fit as well as any of your other garments. The heel should sit on your heel and not under it as in a sock too small, nor half way up your Achilles as in a sock that’s too large. Socks should be flush against your foot with no extra material sagging. The toe seam should lay flat across the top of the toes.
Sock Heel at Your Heel
The sock heel should sit on your heel, not under it or above it.
Flat Toe Seam
The toe seam should lie flat along the top of your toes, not above or below.
Taut Across the Foot
Socks should be taut across your foot with no sagging material.
If you wear a wide shoe size (E+), consider sizing up.
Shoe Size | US Men | US Women |
Small |
– |
3 – 6.5 |
Medium |
7 – 9 |
7 – 10 |
Large |
9.5 – 11.5 |
10.5 – 12.5 |
X-Large |
12 – 14 |
– |
Care Instructions
Machine wash warm. Then tumble dry. No need to bleach, iron or dry clean.
Once you are ready to clean your gear, follow a few simple steps to care for your favorite socks, beanie, and gloves.
How to Care for your favorite bison fiber gearMaterial Composition
Yarn Base Composition
50% American bison down / 50% Merino woolOverall Composition
36% Bison down / 36% Merino wool / 26% Nylon / 2% SpandexOur World-Famous Bison Wool Socks
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OTC Compression Socks | Trekker Bison/Merino Boot Socks | American Field Bison Boot Socks | Pro-Gear Technical - Bison/Silk Boot Socks | Yellowstone Bison/Merino Crew Socks | Pro-Gear Technical - Bison/Silk Crew Socks | American Field (AF) Bison Crew Socks 2022 | Casual Crew 2.0 Bison Fiber Socks | Casual Crew Bison/Merino blend Socks | The B.O.S.S. (Best Overall Short Sock) | Kenai Boot Socks | |
Height | Over-the-calf | Boot 14" | Boot 12" | Boot 12" | Crew | Crew | Crew | Crew | Crew | Ankle | Over-the-calf |
Weight | Midweight | Extra Heavyweight | Midweight | Midweight | Heavyweight | Midweight | Midweight | Lightweight | Lightweight | Midweight | Midweight |
Base-Yarn | 50% American bison down / 50% Merino wool | 45% American bison down / 50% Merino wool / 5% Nylon | 70% American Bison Down / 30% Polyester | 50% American bison down / 50% Silk | 50% American bison down / 50% Merino wool | 50% American bison down / 50% Silk | 70% American Bison Down / 30% Polyester | 33% American bison down / 33% Merino wool / 33% Bamboo | 50% American bison down / 50% Merino wool | 33% American bison down / 33% Merino wool / 33% Bamboo | 33% Bison Down 33% Ultrafine Merino Wool 33% bamboo fiber |
Recommended-Footwear-Type | Just about anything | Waders, Muck Boots, Heavy Boots | Just about anything | Insulated Boots, Cowboy Boots | Short boots, Hikers, Trail Shoes | Just about anything | Short boots, Hikers, Trail Shoes | Athletic Shoes, Short Hikers | Athletic Shoes, Short Hikers | Athletic Shoes | Insulated Boots, Cowboy Boots |
Typical-Use | Non-medical grade compression | Extreme cold climate | Anything, Everything | Skiing, Hiking, Hunting. | Hiking, Hunting, Just a good warm sock | Daily Wear (all climates) | Daily Wear (all climates) | Daily Wear (warmer climates) | Daily Wear | running, golf, shooting sports, daily wear | Fishing/Hunting/Hiking |
Origin | Made in the USA | Made in the USA | Made in the USA | Made in the USA | Made in the USA | Made in the USA | Made in the USA | Made in the USA | Made in the USA | Made in the USA | Made in the USA |
Cushioning | Under foot cushion | Under foot cushion | Under foot cushion | Under foot cushion | Under foot cushion | Under foot cushion | Flat knit (no cushion) | Flat knit (no cushion) | Under foot cushion | ||
Customer Reviews |
Customer Reviews
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S&D Spinning Mill, Millbury, MA, USA
Designed from the Ground Up
The Dearnley Family has been running S & D Spinning since the 1800s. This is one of the last large scale wool mills left in the U.S. and they are absolutely crucial to us keeping our production here in the U.S.