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  • Merino wool blended with nylon and a touch of Lycra® spandex delivers durability and a dependable fit
  • Stretch nylon reinforces the heel and toe areas for durability and comfort
  • Arch band adds support

Made in USA.

View all REI Co-op Men's Hiking Socks

REI membership


Best Use Mountaineering, Hiking
Fabric 78% merino wool/20% nylon/2% Lycra spandex
Sock Height Crew
Sock Cushioning Heavy Cushioning
Moisture Wicking Yes
Gender Unisex

Size chart

Rated 5 out of 5 by from My favorite sock So, I would call myself a bit of a sock snob. I'm almost always cold and have for years worn heavy wool socks daily in addition to my trecking. After trying many other brands, the expedition weight merino wool REI socks are now the only socks I buy. Thorlos are very durable, but don't stay up on my leg very well. They also don't stay as soft wash after wash. Smartwool design is more like the REI sock with thick plush knit and good elasticity, but they wear much faster and are much more expensive. So, from my point of view, you can't go wrong with this sock for daily wear for you fellow hypotherms to expedition/mountaineering for the rest.
Date published: 2007-09-13
Rated 2 out of 5 by from Not what they used to be I bought 3 pair of these about a month ago, and am disappointed with them. I have been wearing the REI Expedition socks for several years now, and have always felt they were the best heavy weight socks on the market. REI has evidently changed their source for these socks since the last time I had purchased any, and they are not as heavy and fluffy as they used to be. I think they are probably still the heaviest merino wool socks on the market, but I'm not as happy with the new version as the old version. I'm getting to the age when the layer of fat on the bottom of my feet is starting to go away, and these socks help make up the cushion the fat layer is no longer providing.
Date published: 2014-09-20
Rated 4 out of 5 by from Not quite the same sock as before The trouble with reviews dating back several years is that the product often changes. These socks, for example, used to be easy to pull on and off. Now, they appear to have more elastic woven in, so they are tighter and harder to get on and off. The sock also feels harder on my skin than prior year models. I used to think this was the best sock in the world. It is still a good sock at a good price, and will last you a long while, but it is not as comfortable or easy to use as before. I mostly use it for hiking and backpacking. You may need a Smartwool liner sock inside if you want to cut down on the blisters. This sock is really thick, so it will only work if your shoe or boot has plenty of room in it.
Date published: 2013-04-29
Rated 5 out of 5 by from Running in snow with no shoes So a couple days ago, we had 13 inches of snowfall, and we were trying to get home. We ended up having to pull the vehicle into a church parking lot right off the main road, because there was no way we could get through the side roads in a van. So we walked/jogged about 5 blocks from there back home. The shoes I was wearing were not meant for snow, and let in tons of snow (which was fine, because I was wearing these socks). I had heard of people running in snow with wool socks, so I decided to take the opportunity to test it. I took off my shoes and jogged a bit wearing just these socks, and believe it or not, my feet felt plenty warm and dry.
Date published: 2015-12-31
Rated 5 out of 5 by from Wonder socks I wear these socks in combo with a Sorel wool felt slipper to hike everything from lake trails to Crestone Needle. I use them on all but the hottest summer days. They provide cushion for long hauls with a pack and minimalist footwear. I have actually done a 3-4 hour run in a snowstorm in JUST these socks (no shoes). The wool is so thick it's warm as can be even when soaking wet. It might sound a bit dramatic, but these socks have allowed me to interact with mountain terrain in a whole new way.
Date published: 2014-02-28
Rated 2 out of 5 by from A bit disappointed My expectations for these socks were not met. I agree with everyone that they have great cushion, which I love, but people have failed to mention that they stretch out, slide down, and become uncomfortable within 3-4 miles hiking. I recently bought two pairs and have found them to be "suitable" (i.e. bearably uncomfortable) for only 6-7 miles; more than 8 miles in them and you're asking for a blister. I used both pairs on a recent trip to Smoky Mountains NP and found that it was best to switch them out after a half day's worth of hiking. I plan to return these and see if there's something else better suited. Of course, this is a single man's review and I don't expect everyone, or even anyone, to have/had the same experience.
Date published: 2016-06-16
Rated 4 out of 5 by from So far they are very good I think these are great socks. I have used them a few times and so far no blisters and no discomfort. I have used them with and without polypropylene liners and I prefer them with. I was concerned that they would be too warm but I was comfortable on a 90*F day hike last week. When these were recommended to me I was told get one size smaller and I did. I would say the same to anyone. They are thick and it is better to have them fit snug than to bunch up. I wear a 12.5 shoe and a 13.5 boot and I bought these in a Large.
Date published: 2013-05-15
Rated 5 out of 5 by from Best Socks in the World As an Army officer, I have worn combat boots nearly every day of my life for the past 16 years. In addition to everyday use, I've also worn boots for countless training and field exercises and have been deployed 5 times (Iraq, Afghanistan, and Africa). During this time, I've come to regard socks as the most important piece of gear I wear and I have embarked on a quest for the perfect sock. I have tested, worn, and owned every hiking sock variant of REI, Thorlo, Smartwool, Wigwam, Fox River and generic Army-issue socks available. Everyone is different, obviously, but for me, the REI Merino Wool Expedition Socks are the best socks I have found. I have worn them in 125 degree temperatures in Kuwait and the Sahara Desert as well as below 0 degree temperatures in the mountains of Afghanistan. I'm now up to about 5 or 6 pairs of REI Expedition socks and I wear them almost exlusively (except when I find another new type of sock to try out...) The reasons I like these socks so much are: 1. They do not shrink or deform in washers, dryers, or unknown-variants of 3rd world country laundry procedures. The Fox River and Smartwool socks seem to shrink and lose "loft" when subjected to some laundry techniques. Generic Army-issue socks are, of course, worthless after several months even with careful laundering. 2. They wick moisture very well in the heat and keep my feet warm in the cold. Even in very hot temperatures, my feet feel comfortable with these socks. When I air them out at the end of the day, or sometimes in the middle of the day, they dry out in what seems like a very short amount of time. I regularly wear a pair for 3 or 4 days in a row & they remain cushy and odor free. Wigwam socks, for example, seem to retain moisture to a greater extent. 3. Since they are so thick and well made, they seem to be more durable than other comparable pairs of socks. The Thorlo Trekking socks, for example, become loose and lose their stretchy-ness over time. Anything less than a "Expedition" or "Trekking" style sock starts developing thinned out wear-points after several months of hard use (even the REI midweight wool hiking socks). But these seem to last long past the point when others wear out. 4. They are just comfortable. They fit my feet well (I have 11.5 size shoes and weart the Large socks), they provide cushion, they regulate temperature, and are the right amount of soft. Furthermore, they retain these characteristics for a very long time. One side note, though, is that these are very thick socks, so you will want to wear boots that have some wiggle room in them. I buy boots based off of how they fit around my REI Expedition Socks. As you may be able to tell, I take socks very seriously, and I highly recommend this pair. In my opinion, it is the best pair on the market.
Date published: 2012-12-27
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I have these socks and am very happy. What are the recommended laundry conditions to keep them that awesome?

Asked by: Socketeer
The Merino Wool Expedition Socks can be machine washed on gentle cycle in warm or cool water. Use mild soap; no bleach or fabric softener. Tumble dry low setting or hang to dry.
Answered by: REIservice
Date published: 2016-10-05

What do the sizes equate to? S, M, L, XL

Asked by: Funtester
Please see the Size Chart on the product page located to the right of the "Choose your size/color" window.
Answered by: REIservice
Date published: 2017-04-15
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