How to Choose Base Layers
REI Co-op Heavyweight Merino Long-Sleeve Base Layer Crew Top - Women's
$99.95
Members get an est. $9.99 in rewards
Get ready for adventures in the cold with our warmest merino wool base layer yet. Made with 100% merino wool, the women's REI Co-op Heavyweight Merino Long-Sleeve Crew top is supersoft on the skin.
- Heavyweight 250 g merino wool offers a soft feel without the scratchiness
- Made with 100% merino wool that naturally wicks away sweat, resists odors and dries quickly
- UPF 50+ sun protection
- Underarm gussets are made for ease of movement
- Shoulder seams are rolled forward to help prevent chafing under pack straps
- Close-to-body fit for optimum performance
- Shirttail hem
- Weight for size S: 7.9 oz. (223 g)
- Locker loop makes it easy to hang this shirt to dry or just keep it off the ground
- Machine wash cold, use wool wash product, do not twist or wring, remove promptly; do not bleach; tumble dry low
- Made in a Fair Trade Certified™ factory
- 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
Imported.
View all REI Co-op Women's Base Layer Tops| Best Use | Multisport |
|---|---|
| Shirt Type | T-shirt |
| Fabric | 100% merino wool |
| Sun-Protective Fabric | Yes |
| UPF Rating | 50+ |
| Moisture Wicking | Yes |
| Quick Drying | Yes |
| Underwear Weight | Heavyweight |
| Sleeve Length | Long Sleeve |
| Gender | Women's |
| Sustainability | Fair Trade Certified™ factory From a Climate Label Certified brand |
REI Co-op Clothing - Women's
| XXS | XS | S | M | L | XL | 1X | 2X | 3X | 0 | 2 | 4 | 6 | 8 | 10 | 12 | 14 | 16 | 18W | 20W | 22W | 24W | 26W | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Numerical Size | 00 | 0-2 | 4-6 | 8-10 | 12-14 | 16 | 18 | 20-22 | 24-26 | 0 | 2 | 4 | 6 | 8 | 10 | 12 | 14 | 16 | 18 | 20 | 22 | 24 | 26 |
| Bust | 31 | 32-33 | 34-35 | 36-37 | 38.5-40 | 41-42.5 | 43-45 | 47-49 | 51-53 | 32 | 33 | 34 | 35 | 36 | 37 | 38.5 | 40 | 42.5 | 45 | 47 | 49 | 51 | 53 |
| Sleeve Length | 29.5 | 30 | 30.5 | 31 | 31.5 | 32 | 32.5 | 33.5 | 34.5 | 30 | 30 | 30.5 | 30.5 | 31 | 31 | 31.5 | 31.5 | 32 | 32.5 | 33.5 | 33.5 | 34.5 | 34.5 |
| Waist | 24.5 | 25.5-26.5 | 27.5-28.5 | 29.5-30.5 | 32-33.5 | 34.5-36.5 | 37.5-39.5 | 40.5-42.5 | 44.5-46.5 | 25.5 | 26.5 | 27.5 | 28.5 | 29.5 | 30.5 | 32 | 33.5 | 36 | 38.5 | 40.5 | 42.5 | 44.5 | 46.5 |
| Hip | 34 | 35-36 | 37-38 | 39-40 | 41.5-43 | 44-46 | 47-49 | 50-52 | 54-56 | 35 | 36 | 37 | 38 | 39 | 40 | 41.5 | 43 | 45.5 | 48 | 50 | 52 | 54 | 56 |
| Inseam | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 |
Sizing Notes
Measurements are stated in inches unless otherwise indicated. Size chart values represent body measurements, not garment measurements. Some women's pants are available in petite and tall sizes. Typically petite sizes fit women 4'11" to 5'3". Regular sizes fit women 5'4" to 5'8". Tall sizes fit women 5'9" to 5'11".
PETITE: Generally, as compared to regular sizes, petite sizes are 2.5 inches shorter in inseam, 1 inch shorter in body length, 1.25 inches shorter in sleeve length and Âľ inch shorter in total rise.
TALL: tall sizes are 3 inches longer in inseam, 2 inches longer in body length, 2.5 inches longer in sleeve length and 1.25 inches longer in total rise.
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
Love this base layer top
PNWkiwi9 months ago
Received free productI was prepared to be disappointed because I haven't had much luck finding a base layer that doesn't make me feel claustrophobic and itchy. I was really surprised by how soft it feels and the fit is slim but not skin tight, with enough room to be active but still add layers. The fit is so nice I happily wear it as an outer top. I have washed and dried it multiple times and it still looks good and isn't pilling. Most importantly, it doesn't seem to trap my hair or dog fur on it like a lot of base layers. I was also impressed that it didn't make overheat during a hot flash and made it less of a stressful of a situation. I will be buying more of these.
PNWkiwiReceived free product
Portland, Oregon
8 people found this review helpful
Most Helpful Critical Review
Disappointing quality
Katfr87 months ago
I bought this shirt about 1 month ago and was pleased with the fit and weight as compared to my Smart Wool shirts. However several wearing and one cold wash later, several small holes appeared in the front of the shirt. As a long time REI member, I’m very disappointed in the poor quality and in the future will pay a little more and stick with Smart Wool. Should have returned!
Katfr8
4 people found this review helpful
Customer Images
weebok327
Received free product
Fantastic heavyweight shirt
8 months ago
I've worn this multiple times - hiking, doing yard work, running errands on freezing midwest mornings. This baselayer is soft and warm without making me too hot when I venture indoors. I'm a standard 6 and the medium fits me like a glove and doesn't ride up when I move around. The seams are flat to prevent chafing, there's a side gusset so you can move without feeling constricted, and it's machine washable and can go in the dryer! The shirt feels substantial and high-quality. Even after multiple wears, there's no sign of thinning or pilling, even in the armpits.
Weight:150–175 lbs.
Height:5'5"
Yes , I recommend this product
fern
Received free product
Nice basic, perfect for cool fall and winter runs
9 months ago
I wore on rainy cold runs - stayed warm, but didn't overheat. It would also layer nicely under a vest or jacket for snowshoeing or active winter sports. Wool is soft, not at all itchy (and no scratchy labels!) There is a nice little cord at the back of neck for hanging to dry. Washed up well, I didn't notice any shrinking. According to size charts I would be a small, but I ordered a medium because I prefer relaxed fit and extra sleeve length to pull over my hands. I would love some brighter jewel tone color options, but black is a fine basic. This will get a lot of wear around here.
Weight:100–125 lbs.
Height:5'5"
Yes , I recommend this product
JSDY
Received free product
For when you’re looking for a weightier base layer
8 months ago
At first glance I wasn’t that excited to try it on. It looked like it was going to be rough on the skin so my expectations were low when I put it on for the first time. I was pleasantly surprised to find it very comfortable on the skin, not rough at all. The shirt has some weight to it so it felt substantial, by which I mean I did think it a little on the heavier side for a base layer but there might be times when this is what I’d want. The cut was flattering though perhaps it runs a little small and I was sure it would shrink with the first wash but it held its size. I’ve actually worn it as a shirt, it’s versatile enough with a pair of jeans and is now on regular rotation in my closet.
Yes , I recommend this product
MinnieCO
Received free product
Fort Collins, CO
Light and comfy
9 months ago
This base layer is comfortable and fits well. The material is not itchy at all and can be worn as a shirt on its own on cooler days. I like the way it falls on me, with a curved hem on the front and back so it gives a bit of bum coverage over leggings. The material is lightweight but doesn’t feel thin. I am 5’3”, 110lbs and the small was a perfect fit. I am careful not to dry it in the dryer so that it won’t shrink or wear out quickly.
Age:35–44
Weight:100–125 lbs.
Height:5'3"
Yes , I recommend this product
PNWkiwi
Received free product
Portland, Oregon
Love this base layer top
9 months ago
I was prepared to be disappointed because I haven't had much luck finding a base layer that doesn't make me feel claustrophobic and itchy. I was really surprised by how soft it feels and the fit is slim but not skin tight, with enough room to be active but still add layers. The fit is so nice I happily wear it as an outer top. I have washed and dried it multiple times and it still looks good and isn't pilling. Most importantly, it doesn't seem to trap my hair or dog fur on it like a lot of base layers. I was also impressed that it didn't make overheat during a hot flash and made it less of a stressful of a situation. I will be buying more of these.
Age:45–54
Weight:150–175 lbs.
Height:5'2"
Yes , I recommend this product
sd2102
Received free product
PNW
Comfy baselayer
9 months ago
I'm surprised by how soft and comfortable this shirt is, it feels as soft as cotton but warmer and better wicking. I've worn it for short hikes and gardening, and to keep warm in my drafty old home! I find myself reaching for it more often than I expected. It's a bit long on my short frame, but perfect to wear over leggings and to tuck in with other pants.
Age:45–54
Weight:100–125 lbs.
Height:5'2"
Yes , I recommend this product
camiv96
Received free product
Great, more affordable option w/ some sacrifices
8 months ago
I absolutely love my merino wool base layers and swear by them. I really appreciate that this has such a high merino wool content instead of just containing some - it really does make all the difference. This has done a great job of wicking away sweat and keeping me warm during cold weather adventures, even post sweat. The fit is mostly flattering. I do prefer my base layers to be form fitting so it doesn’t cause uncomfortable wrinkling; this one runs large for its size. However, I would also prefer that the sleeve length was about an inch longer (I am only 5’3” and it feels short). I do love the armpit gussets as other similar shorts have gotten holes there before, and this allows more overhead flexibility.
Weight:125–150 lbs.
Height:5'3"
Yes , I recommend this product
Long sleeve wool top
Received free product
Raleigh NC
Loved this warm versatile top!
9 months ago
I received this too right before I took a trip to Europe in November. It was quite cold, lows in the low 30’s and highs in the low 40’s. The top came in handy for keeping me warm. I wore it quite a lot and really loved it!
Age:55–64
Weight:100–125 lbs.
Height:5'2"
Yes , I recommend this product
Phuong
Huntington Beach
Hit or Miss
7 months ago
I owned two of these shirts in different colors (black and Jasper). They were true to size, and offered a snugger fit that wasn’t too loose. I wore both shirts during the week and washed them together in the same cycle (delicate, with wool detergent, cold water), then line-dried and stored them the same way. The black shirt held up perfectly after multiple washes, but the Jasper developed holes—one on the sleeve and another on the back. I’m not sure if the Jasper was defective or if there’s a difference in quality between the colors. After almost three months of owning the Jasper shirt, I brought it back and exchanged it for another one to see if the issue was specific to the color or a one-off defect.
Age:25–34
Weight:100–125 lbs.
Height:5'2"
Yes , I recommend this product
Katfr8
Disappointing quality
7 months ago
I bought this shirt about 1 month ago and was pleased with the fit and weight as compared to my Smart Wool shirts. However several wearing and one cold wash later, several small holes appeared in the front of the shirt. As a long time REI member, I’m very disappointed in the poor quality and in the future will pay a little more and stick with Smart Wool. Should have returned!
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