How to Choose Base Layers
REI Co-op Midweight Long Underwear Bottoms - Men's
This product is not available. Good news: we have a newer version.
Excellent flexibility and moisture control make the men's REI Midweight Long Underwear Bottoms an outstanding choice for a wide range of activities in cool conditions.
Shop newer version- 4-way-stretch polyester fabric wicks moisture off skin and dries fast to prevent you from feeling chilled or clammy; brushed inner surface feels soft and warm
- The fabric also has a UPF 50+ sun protection rating
- Space-dye process produces a textured color that's unique to each garment
- Nonchafing flatseam construction and elastic waistband increase comfort as you move
- Smooth outer surface slides easily under other layers
- The men's REI Midweight Long Underwear Bottoms have a functional fly and a next-to-skin fit that hugs the body for optimum performance
- 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
| Best Use | Snowsports Hiking |
|---|---|
| Fabric | Polyester |
| Sun-Protective Fabric | Yes |
| UPF Rating | 50 |
| Moisture Wicking | Yes |
| Quick Drying | Yes |
| Underwear Weight | Midweight |
| Inseam (in.) | 32 inches |
| Gender | Men's |
| Sustainability | 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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Location:Monterey, CA, United States
11 years ago
Keeps you warm and dry
Yes , I recommend this product
I bought these for my boyfriend as I have several pair of the women's version. I love these for snowboarding, backpacking, or just working outdoors in the colder months. I often wear these for yard duty on cold days under my slacks. These are very light weight and very warm. These keep you very dry for perspiration while climbing in the deep snow in search of fresh pow.
Location:Kansas City, MO, United States
10 years ago
Great layering!
Yes , I recommend this product
I bought this to withstand the uber cold of the KC Chiefs games. They also work great as a sheek layer under my slacks. The matching tops are super warm too. So far, no issues with them.
Location:Fremont, CA, United States
11 years ago
Long Underwear with flair
Yes , I recommend this product
I have similar long underwear that is either gray and black and these share the same benefits of warmth and freedom of movement when hiking or climbing, but there is something about the color that makes it fun to wear, as well.
Location:Bellingham, WA
11 years ago
Retains moisture
No, I do not recommend this product
Felt good, seemed to fit fine... BUT they retain moisture. I planned to use them for ocean kayaking under a drysuit. Once the got damp, they stayed damp unlike most other fleece that I own.
9 years ago
Great buy, easy wear
Got these on sale. These things are amazingly cozy and warm. I normally wear long underwear all winter and these have easily become my go to. Wicks great and keeps me warm when needed. Even in colorado where it can be 32 degrees one minute and 70 the next these have kept me in the right temp.
Location:Baltimore, MD
10 years ago
Nice Pair of Thermal Bottoms
Just bought these for a recent trip, on the A.T for 4 days. Only got down to the high 30's one night, but i was warm in these. They were a little tight in the thigh, but otherwise comfortable and warm. Maybe a little on the pricey side for thermal underwear, but they work.
Location:St. Louis
9 years ago
Great long underwear
I bought a couple pairs of these long underwear for my husband and he loves them so much that a bought a few more. He wears them under his pants and jeans when the weather is cold out. He says that they are comfortable and fit true to size.
3 years ago