How to Choose Base Layers
REI Co-op Midweight Base Layer Bottoms - Men's
$54.95
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An ideal performance layer, the men's REI Co-op Midweight base layer bottoms boast a smooth face and low-bulk seams for easy layering and a brushed back for added warmth and comfort.
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- Recycled polyester/spandex fabric has a smooth face so layers slide on easily and is peached for a supersoft next-to-skin layer
- Spandex adds the right amount of stretch combined with a crotch gusset to maximize your range of motion
- Fabric wicks moisture to keep you comfortable and dry
- 4-way stretch delivers a flexible range of motion
- Flatseam construction and a soft elastic waistband reduce bulk and chafing
- UPF 50+ rating protects against sun rays
- Inseam length: 28 in.; Tall sizes: 31 in.
- Average garment weight: 7.2 oz.
- Machine wash cold, wash separately, gentle cycle, remove promptly; do not use bleach or fabric softeners; tumble dry low
- REI Co-op brand is certified to The Climate Label; we actively fund efforts to reduce carbon emissions across our business and support climate projects around the world
- Made in a Fair Trade Certifiedâ„¢ factory
- Contains materials that meet the bluesign® criteria
Imported.
View all REI Co-op Men's Base Layer Bottoms| Best Use | Multisport |
|---|---|
| Fabric | 92% recycled polyester/8% spandex (bluesign approved) |
| Sun-Protective Fabric | Yes |
| UPF Rating | 50 |
| Moisture Wicking | Yes |
| Fly Opening | Yes |
| Underwear Weight | Midweight |
| Inseam (in.) | 28, 31 inches |
| Gender | Men's |
| Sustainability | Fair Trade Certified™ factory Contains materials that meet the bluesign® criteria Contains recycled materials From a Climate Label Certified brand |
REI Co-op Clothing - Men's
| XS | S | M | L | XL | XXL | XXXL | 24 IN Waist | 26 IN Waist | 28 IN Waist | 30 IN Waist | 31 IN Waist | 32 IN Waist | 33 IN Waist | 34 IN Waist | 35 IN Waist | 36 IN Waist | 38 IN Waist | 40 IN Waist | 42 IN Waist | 44 IN Waist | 46 IN Waist | 48 IN Waist | 50 IN Waist | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chest | 35 | 36 - 38 | 39 - 41 | 42 - 45 | 46 - 49 | 50 - 53 | 54 - 57 | |||||||||||||||||
| Sleeve Length | 32 | 32.5 | 33 | 33.5 | 34 | 34.75 | 35.5 | |||||||||||||||||
| Waist | 27.5 | 28 - 30 | 32 - 34 | 36 - 38 | 40 - 42 | 44 - 46 | 48 - 50 | 24 | 26 | 28 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 38 | 40 | 42 | 44 | 46 | 48 | 50 |
| Hip | 33.5 | 34.5 - 36.5 | 37.5 - 39.5 | 41 - 43 | 44 - 46.5 | 47.5 - 50.5 | 51.5 - 54.5 | 32 | 33.5 | 34.5 | 36.5 | 37 | 37.5 | 38.5 | 39.5 | 40.25 | 41 | 43 | 44 | 46.5 | 47.5 | 50.5 | 52.5 | 54.5 |
| Inseam | 32 | 32 | 32 | 32 | 32 | 32 | 32 | 32 | 32 | 32 | 32 | 32 | 32 | 32 | 32 | 32 | 32 | 32 | 32 | 32 | 32 | 32 | 32 | 32 |
Sizing Notes
Measurements are stated in inches unless otherwise indicated. Size chart values represent body measurements, not garment measurements.
SHORT: Some pants are available in short sizes, which generally means an inseam that is 2.5 inches shorter than regular sizes.
TALL: Some pants, shirts, jackets and parkas are available in tall sizes, which generally means an inseam that is 3 inches longer and a rise that is 1 inch longer, a shirt or jacket body that is 2 inches longer, a parka body that is 2.5 inches longer and sleeves that are 2.5 inches longer than regular sizes.
Capri or cropped pants have an intentionally shorter inseam—reference the technical specs instead of this chart.
Inseam is measured to the floor.
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Most Helpful Favorable Review
Comfortable, durable, and does drag on clothing!
Nathan H2 years ago
Received free productI have several base layers from various companies. I have been using them for years and in various conditions. I can say these ones are the most comfortable so far! They also had the least amount of resistance and drag when they were put under my hiking pants. They were worn on the day they arrived and felt the same after being washed two times = seriously comfortable!
The best tests so far took place on 28 September 2022 when I hiked Willow Lake. I wore them under my Kuhl outfit. They pants worked great and were not too restrictive when I was running up the trail to the lake and when I was walking down the trail. They provided warmth when a thunder storm moved in that night and did not snag on my pants or restrict movement when there was some moisture in my clothing. They were slightly warm when I started the hike and the temperature was about 65. They were perfect at the end when the temperatures were in the 50's.
The pants were also tested on 2 October 2022 when I went up Provo Canyon to take pictures of the fall leaves. It was in the 60's when I was up there and wore them under my Kuhl Law Pants. The layer was washed 2x by that time and it still felt like new. No signs up bubbling or wear. I wandered for over 10 miles while taking pictures and the layer worked great with this outfit. My law pants are more rigid and thick than my other Kuhl pants. The base layer still did great, did not snag, and did not restrict movement. I was a little warm when I was in the sun, but the layer did great in the shade. I was a bit sweaty because I was wearing a few layers. The base layer did a great job wicking sweat and I was surprisingly dry on the drive home.
These appear to be good base layers for medium temperature use. I wouldn't wear them if it's above 65. Not sure how warm they will be under 40. They did not seem quite as warm as my Under Armour Base Layer 3 outfit. They definitely seem about the same warmth as my regular Under Armour Cold Gear Infared outfit (inbetween Base Layer 1 and 2).
I also wore them while resting in my Klymit sleeping bag the other day. Super comfortable.
Nathan HReceived free product
Draper, UT
36 people found this review helpful
Most Helpful Critical Review
Not as good as the past
Keith2 years ago
Warm but not durable. Previous line of same brand/weight was superior. I wear base layers for work. After a couple of wears and already showing fatigue. Previous set, a couple years old and still withstanding.
Keith
28 people found this review helpful
Customer Images
Nathan H
Received free product
Draper, UT
Comfortable, durable, and does drag on clothing!
2 years ago
I have several base layers from various companies. I have been using them for years and in various conditions. I can say these ones are the most comfortable so far! They also had the least amount of resistance and drag when they were put under my hiking pants. They were worn on the day they arrived and felt the same after being washed two times = seriously comfortable! The best tests so far took place on 28 September 2022 when I hiked Willow Lake. I wore them under my Kuhl outfit. They pants worked great and were not too restrictive when I was running up the trail to the lake and when I was walking down the trail. They provided warmth when a thunder storm moved in that night and did not snag on my pants or restrict movement when there was some moisture in my clothing. They were slightly warm when I started the hike and the temperature was about 65. They were perfect at the end when the temperatures were in the 50's. The pants were also tested on 2 October 2022 when I went up Provo Canyon to take pictures of the fall leaves. It was in the 60's when I was up there and wore them under my Kuhl Law Pants. The layer was washed 2x by that time and it still felt like new. No signs up bubbling or wear. I wandered for over 10 miles while taking pictures and the layer worked great with this outfit. My law pants are more rigid and thick than my other Kuhl pants. The base layer still did great, did not snag, and did not restrict movement. I was a little warm when I was in the sun, but the layer did great in the shade. I was a bit sweaty because I was wearing a few layers. The base layer did a great job wicking sweat and I was surprisingly dry on the drive home. These appear to be good base layers for medium temperature use. I wouldn't wear them if it's above 65. Not sure how warm they will be under 40. They did not seem quite as warm as my Under Armour Base Layer 3 outfit. They definitely seem about the same warmth as my regular Under Armour Cold Gear Infared outfit (inbetween Base Layer 1 and 2). I also wore them while resting in my Klymit sleeping bag the other day. Super comfortable.
Age:35–44
Weight:150–175 lbs.
Height:5'8"
Yes , I recommend this product
Tadoerner
Received free product
Cincinnati, OH
Comfortable and roomy- great mid-layer for camp!
2 years ago
I am 200 pounds, 6'1" on a good day, waste size 36-38. I decided to size up to the XL and am thankful I did. Although the elastic waste band was a bit too loose for my liking, these tapered down quite comfortably over the calf and ankles while leaving enough room for ease of mobility around the inner thigh area. If I had a size L, I would be curious/concerned how tight they would fit over the ankles. I don't consider these as a "next to skin" base layer, but more of a very comfortable mid layer to make camp and sleep in. Very good value for the money. I slept in sub 40 deg F conditions with a 35 degree sleeping bag and was cozy all night long....never felt the notorious "itchy" seems rubbing against my skin. These did not make me feel constricted like a next to skin layer would, but there is plenty of room to add that type of base layer in if the weather requires it. Only reason I don't give 5 stars right now is because I am not sure how the elastic waste band will hold up over time (3-5 years).
Age:25–34
Weight:200–225 lbs.
Height:6'0"
Yes , I recommend this product
shaner41
Received free product
wisconsin
Excellent Midweight Base Layer!
2 years ago
Since moving to Wisconsin some years ago I've learned to really appreciate base layers. I wear base layers for various activities around 5 months of the year. These "REI Co-op" men's midweight bottoms are very accurately described. They are midewight. They're not thin and light for warmer days, but they're not super thick for cold winter days. I'd say they're good for weather in the 30's or 40's, depending on your activity. I went for a run with them on a 50 degree day and they were too warm for that. But on a bike ride going fast they were OK in 50 degree weather. I'd also wear them under jeans on regular cold winter days. And yes, they are comfortable - soft and not scratchy. The large fits me as it should - I usually wear a large. So far they have not shrunk when I washed them following the instructions. Note: they are not compression bottoms, but that's fine with me, just mentioning it in case someone was wondering.
Age:35–44
Weight:175–200 lbs.
Height:6'0"
Yes , I recommend this product
Mike
Received free product
USA
A great midweight layer for the shoulder season
2 years ago
I have experience using the REI lightweight base layer so I was curious to see if these mid-weight would be a more ideal choice for fall/spring backpacking, which is what I primarily use them for. I use baselayers for sleep clothes mostly, but also for cold mornings/days and I hike with them if need be. These were great for adding an extra tier of warmth, which is noticeable. They breathe well and wick moisture well, overall construction is very good quality, just like the lightweight ones I already had. I will say I prefer the tall-fit to the standard fit I received.
Age:35–44
Weight:175–200 lbs.
Height:6'3"
Yes , I recommend this product
Keith
Not as good as the past
2 years ago
Warm but not durable. Previous line of same brand/weight was superior. I wear base layers for work. After a couple of wears and already showing fatigue. Previous set, a couple years old and still withstanding.
BareGrillz
Michigan
Long Underwear for Fall :(
1 year ago
Disappointed is probably the best word for these. Having bought 3 other pairs over the years I thought I knew what I would be receiving. Unfortunately these are nothing more than LIGHTWEIGHT base layer bottoms labeled as Midweight. About half the thickness of my previous 3 pairs all ordered using this same REI item (Order History) and description. Much more like tights, very tight to the body and thinner material. Probably best for Spring/Fall cool weather as they dont help much during this Michigan Winter.
Age:45–54
Weight:175–200 lbs.
Height:5'9"
No, I do not recommend this product
Bobby1080
New York NY
Excellent investment
2 years ago
This is my second pair of REI leggings and I'm just as happy with these as I have been with my other pair. I wear these to bike ride riding in NYC during the winter. I have worn these as standalones with a pair shorts over them in 50 degree temps, in the 40's and into the 30's. My legs handle cold better than my upper body so take that into consideration if you are thinking of wearing these as solo garments in 30 degree or colder temps. You may need pants over them depending on how hot or cold you run. The amount of warmth and protection I receive is fantastic. The wind resistance isn't bad either. The fit and flexibility is superb. I have full range of motion when riding, walking and stretching. I am 5'7 about 150 lbs, 33-34 waist and the Medium fits perfectly. The length comes down to about my ankles. I typically bring a change of clothes to work so I can ride home and because they are so effective, it has saved me from packing pants to this point.
Age:45–54
Weight:150–175 lbs.
Height:5'7"
Yes , I recommend this product
ghav
Dry and scratchy. Not the same as previous
2 years ago
Smaller size, not stretchy, and made out of a dry, scratchy material. It's disappointing when you think you are buying another of the same great product, but it's been changed or cheapened for the worse. My previous pair was smooth and soft. Happening with several REI brand shirts and tights.
No, I do not recommend this product
Rob6
Received free product
Baltimore, MD
Very comfortable!
2 years ago
The first thing I noticed about these is that they don't have the "plasticky" feel of many synthetic base-layers. These feel more like a soft merino fabric. It's still too warm to need base-layers, but I've worn them for several days straight and they have really breathed well. I've never over-heated or gotten that "swampy" feeling. Another plus is that they haven't developed any unpleasant odors. It's too early in the season to know how warm they will be, but based on my experience so far, I'm optimistic. I normally wear medium, but got these in a large and am not disappointed. They are still "next-to-skin" fit, but don't feel restrictive. Overall, they're really comfortable and have held up well. The only reason for a 4-star is not knowing yet how warm they will be in really cold weather (it was in the 80's when I first got them, and now it's in the 60's-70's F) or how durable they will be over the long haul. Can't wait to try them out when it gets colder.
Age:55–64
Weight:175–200 lbs.
Height:5'9"
Yes , I recommend this product
Sparks
Nomad
WITHSTOOD THE SUBARCTIC
2 years ago
I took these to the subarctic during the peak of winter, and wore them on 10-15km hikes through rolling hills and over frozen lakes. They kept me warm in conditions of -10 Fahrenheit.
Age:25–34
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