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  • Smartwool - Mountaineering Extra Heavy Crew Sock - Charcoal Heather
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  • Smartwool - Mountaineering Extra Heavy Crew Sock - Charcoal Heather
  • Smartwool - Mountaineering Extra Heavy Crew Sock - Taupe

Smartwool Mountaineering Extra Heavy Crew Sock


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    29 Reviews


    Comfortable feet in uncomfortable conditions.

    When you're high up on the mountain, the last thing you want to worry about is your feet. Wear the Smartwool Mountaineering Extra Heavy Crew Sock, and just worry about bagging that summit. This crew-length sock utilizes Smartwool's wool-on-wool technology for maximum extra-heavy cushioning and durability. A flat-knit toe seam helps to avoid irritation inside your boot, and Smartwool's fit system gives added arch and ankle support.

    • WOW wool-on-wool technology
    • Extra-heavy cushioning
    • 2x1 ribbed knit cuff
    • Flat knit toe seam
    • Smartwool fit system
    • Item #SWL005L
    • Reviews
    • Q & A

    What do you think about this product?

    Have questions about this product?

    Worth the dough

    • Familiarity: I've used it several times

    Very comfortable and very warm, you can wear them under 40 degrees if you are a hot body and under 50 if you are a cold bodied person. They wash well and have held up under multiple washes and many miles of hiking. Long term is uncertain but I have had multiple of their products before that speak for themselves. $24 is a steep price but its worth it, especially if you can get it on sale.

    Quality- 10/10
    Comfort- 10/10
    Cost- 7.5/10
    Practicality- 9/10
    Value- 9/10
    My final conclusion is that I would recommend them and nothing better is on the market that I've found.

    Thick, warm and high quality

    • Familiarity: I've used it once or twice and have initial impressions

    What more do you need in great socks? These are well made and do exactly what they should. The elastic is nice and they seem like they will last a long time.

    Coziest Socks Ever!

    • Familiarity: I've put it through the wringer

    In trying to follow the Danish concept of Hygge, I bought these socks to embrace all that is cozy! These are the plushest socks I could find and I absolutely love them! They are super warm and the heavy padding gives your feet the sweet relief they deserve. Do yourself a favor and get these socks, you will not be disappointed.

    Doesn't Get Better

    • Familiarity: I've put it through the wringer

    Bought these for my wife and I don't think there has been one day since I bought them for her that she has not worn that for at least part of the day. Incredibly warm and comfortable while also durable and long lasting. We've tried tons of different types of warm socks in the past and no one has been able to compare to smartwool.

    Simply Awesome Socks

    • Familiarity: I've used it several times

    I can't say enough how great these socks are. Extremely comfortable, very warm and does a great job of keeping your feet dry even if your feet start to heat up a bit.

    That's a thick sock

    • Familiarity: I've put it through the wringer

    If you are looking for a pair of thick wool socks that will keep your feet warm look no further. These pair well with any winter boot to keep the wet, cold winter out and the heat in. Wear them around the house and they double as a light slipper. I was so impressed by the softness and the warmth I bought a couple of pair for gifts. I love Smartwool socks for their durability, and these continue the tradition. Strong, warm socks for any chilly day.

    Don’t forget your boots!

    • Familiarity: I've put it through the wringer

    I am a Smartwool diehard, had many pairs of most styles, but these are the best. They are insanely thick and warm. You might have to loosen the laces on your kicks to slip your feet in with these socks on. I have walked around camp in the snow with out my boots in these socks, that is how thick and warm they are! Killer around the house on winter mornings on the hardwoods too.


    • Familiarity: I've put it through the wringer

    These socks did a very nice job keeping my feet warm during the winter . I had no trouble walking around all day. The socks are very soft and provide cushion and support, I had no trouble with blisters or any discomfort. The moisture control kept my feet dry throughout the day.more pairs and recommended it to friends as well.

    Like Wearing Sheep on your Feet

    • Familiarity: I've put it through the wringer

    These socks are a cold weather must! They are thick wool socks to help wick moisture away while still keeping your toes nice and toasty. The extra padding on the footbed helps to provide extra cushion when you are hiking, as well as lounging around the house or winter camping!

    Beastly sock wear

      Can't imagine a better mountaineering sock. Built to last and keep your protected from the environment. Definitely has handled everything I've thrown at it plus while lounging they are the epitome of comfort. Well worth the price tag and will keep you adventuring probably until you lose them or a bear gets you. Backcountry got it to me super fast as always with no hassles. #goatworthy

      Great Sock

      • Familiarity: I've put it through the wringer
      • Fit: True to size
      • Size Bought: Small

      I really love these socks, they have kept my feet warm in mountaineering boots many times. They are very cushy and fit well. They are really thick and I definitely recommend them if you are going on any mountaineering trip!

      Great hiking socks

      • Familiarity: I've put it through the wringer
      • Fit: True to size
      • Size Bought: medium
      • Height: 5'9"
      • Weight: 165lbs

      I have used these many times for work and hiking and I love them. They provide a great amount of cushion in all the necessary places which is awesome for the long days. I have used these on 10-20 mile hikes, as well as 18+ hour work days and they worked perfectly for me.

      The only sock for me.

      • Fit: True to size

      Love these things. Super good padding, keeps the blisters to a minimum. Awesome at keeping the toes warm when walking through the snow and wicking away sweat on those hot days too. They last forever too!!!

      like wearing a whole sheep on your feet

      • Familiarity: I've put it through the wringer
      • Fit: True to size
      • Size Bought: large
      • Height: 5'5"
      • Weight: 121lbs

      They sure are heavy. And warm. And cushy.
      I use them when running outside (in minus 25 degrees) and when I get home with ice cold feet from a long day split boarding; instant warmth.

      Just as described.

      • Familiarity: I've put it through the wringer
      • Fit: True to size

      I was looking for the warmest, thickest socks I could find, and these are it.
      These socks are warm, thick and comfy. I use them as slippers in my house to keep my feet warm walking on cold tile, I use them snow shoeing, snowmobiling, skiing, sledding, and occasionally I sleep in them.
      The only unsatisfactory issue one might find with this sock, is they do not stay on the calf as well as one might want. I've noticed that they do tend to slide down my leg. This only happens with I'm not wearing a boot of some kind. They stay up find in a boot or shoe.
      Perfect sock, I'll probably buy way more than I need.