REI Co-op Midweight Base Layer Bottoms - Kids'
A thermal base layer that wicks for warmth, the kids' REI Co-op Midweight base layer bottoms help keep them comfortable for all-day exploring and adventuring in colder weather.
- Durable recycled polyester/spandex blend fabric is soft and sweat-wicking
- 257 g/m2 fabric weight offers midweight warmth
- UPF 50+ sun protection
- Low-profile waistband keeps kids comfortable as they move
- Designed to hug the body for optimum performance
- Soft, durable flatlock seams are smooth and comfortable
- Size S Kids has an inseam length of 21.75 in.
- Size M (10–12) Kids has a weight of 5.1 oz. (144 g)
- Machine wash separately in cold, gentle cycle, remove promptly; do not use bleach or fabric softeners; tumble dry low
- Note: not intended for sleepwear
- 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
- Contains materials that meet the bluesign® criteria
Imported.
View all REI Co-op Kids' Base Layer Bottoms| Best Use | Multisport |
|---|---|
| Fabric | 87% recycled polyester/13% spandex (bluesign approved) |
| Sun-Protective Fabric | Yes |
| UPF Rating | 50 |
| Moisture Wicking | Yes |
| Underwear Weight | Midweight |
| Inseam (in.) | 21.75 inches |
| Gender | Kids' |
| Sustainability | Contains materials that meet the bluesign® criteria Contains recycled materials From a Climate Label Certified brand |
| XXS | XS | S | M | L | XL | |
|---|---|---|---|---|---|---|
| Numerical Size | 5 | 6-7 | 8 | 10 | 12 | 14 |
| Height Range | 45 | 47 1/2 - 50 | 52 | 57 | 61 1/2 | 65 1/2 |
| Across Shoulder | 11 | 12 1/4 | 13 | 13 1/2 | 14 | 14 3/4 |
| Chest | 23 | 24 - 25 | 26 - 27 | 28 - 29 1/2 | 30 1/2 - 31 1/2 | 32 - 33 |
| Sleeve Length | 21 | 22 - 23 1/2 | 24 - 25 | 26 - 27 | 27 1/2 - 28 1/2 | 29 1/4 - 30 1/4 |
| Waist | 21 1/4 | 22 - 23 | 24 - 25 | 26 - 27 | 27 1/2 - 28 1/2 | 28 3/4 - 29 3/4 |
| Hip | 23 3/4 | 24 1/4 - 26 1/4 | 27 - 28 | 29 - 31 | 32 - 33 | 34 - 35 |
| Inseam | 19 | 21 - 22 3/4 | 23 - 24 | 25 - 26 1/2 | 27 - 29 | 29 1/2 - 30 1/2 |
Sizing Notes
Measurements are stated in inches unless otherwise indicated. Size chart values represent body measurements, not garment measurements.
Inseam is measured to the floor.
Better gear is built together
From feedback to field testing, all of our gear is dialed-in by REI Co-op members. Their adventures informed every stitch and detail—making for better, longer-lasting gear.
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Warm, comfortable midweight baselayer
Overall my tall 8 year old son was happy with these. They are midweight warmth and comfortable on the skin. He is fairly picky about texture so that was a big plus. They seem to breathe reasonably well. We ended up getting an XL instead of a L so they are rather baggy but that didn't seem to bother him.
Good winter layer for kids.
I got these for my daughter for winter hiking and snow sports. I don’t think any kid is absolutely psyched on long underwear but she doesn’t seem to mind them. They have worn quite well and don’t seem to have any of the funky smell you can get with synthetics. They layer well under snowpants and are loose and comfortable enough that she wears them when at home after being outside.
The best base layers for your winter fun!
These base layers are awesome for all your family's outdoor adventures together! These are great fitting, not itchy at all, keep my boys warm enough throughout the day and they wash and dry perfectly. My kids like that they're not itchy like the wool base layers. They're versatile for so many activities and the price is a great value for the product you get.
Great mid-weight base layer for kids
These are for my 13-year-old son who is about 5’6”. As you can see by the pictures, he has plenty of room to grow into them in both length and girth. They don’t fit snug but that is okay because he mostly wears them for camping and as pajamas in the winter. We’ve been buying these pants for our kids since they were toddlers, and they have remained good quality. His old pair does have a hole in the knee but that is because he wore them around the house and played in them. These pants are warm, comfortable and sturdy and great as a mid-weight base layer.
Great, lightweight base layer
REI Trailblazers allowed us to review these base layer bottoms. My 11 year old son tested them and LOVES them; he would wear them everyday if he could. These pants are a great base layer as they are thin enough to fit under other layers. Being as thin as they are, they are great as a lighter layer, and don't provide too much additional warmth.They don't bunch up or snag on other layers. We are reviewing the gray color, which is a fine color, but, when worn as lounge pants, I wish the color was a little darker.Overall, these pants are great as a light layer for extra warmth and comfort.
Nice Thermals
Fine for thermals. Nothing fancy or exceptional about them.