How to Choose Base Layers
REI Co-op Merino 185 Base Layer Top - Men's
$69.95
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Hike, bike and even sleep in the men's REI Co-op Merino 185 short-sleeve base layer top. The soft, breathable and naturally odor-resistant ultrafine merino wool makes it an ideal next-to-skin layer.
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- Ultrafine 185 g merino wool offers a soft feel without any itchiness
- Made with 100% merino wool that naturally breathes, wicks away sweat, dries quickly and resists odors, making it an ideal multiday trip companion
- UPF 30 sun protection
- Flat seams and merrow stitch construction eliminate chafing
- Underarm gussets allow full range of movement
- Designed to hug the body for optimum performance
- Weight: 6 oz.
- Machine wash warm, gentle cycle, with wool wash product; do not twist or wring; remove promptly; do not bleach; tumble dry low; dry cleaning not recommended
- Field-tested on its own and as a base layer while hiking, running, rock climbing, cycling, skiing and camping in diverse climates across the U.S.
- 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 Certified™ factory
Imported.
View the REI Co-op Merino 185 Product LineView all REI Co-op Men's Base Layer Tops| Best Use | Multisport |
|---|---|
| Shirt Type | T-shirt |
| Fabric | Merino wool |
| Sun-Protective Fabric | Yes |
| UPF Rating | 30 |
| Moisture Wicking | Yes |
| Quick Drying | Yes |
| Underwear Weight | Lightweight |
| Sleeve Length | Short Sleeve |
| Gender | Men's |
| Sustainability | Fair Trade Certified™ factory 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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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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Most Helpful Favorable Review
Light, breathable, no chafing, good color
Prairie Dog4 years ago
Received free productI'm pretty impressed with this base layer top. In the first two weeks I had it, I took it on three excursions: a c. 10-mile bike ride and two hikes.
On the ride, it was about 75 with high humidity. Roughly 4 miles into the ride, it started raining and I had to put on my rain jacket. The jacket went over both my shirt and my backpack, so I worried that I would get very wet from the inside despite the pit zips in my jacket. While I did get a bit wet, I was notably drier than I anticipated.
On the two hikes - one in a nearby forest preserve in the mid-80s and high humidity with no breeze (let's hear it for summer in Chicago) and the other in high 80s with high humidity and a fair breeze (Black Hills, starting at about 6200 feet of elevation and going up to about 6600), I had a 40 L backpack, and carried about 20 lbs of gear for the family and a couple liters of water.
Pros: It's breathable, kept fairly dry during each of the hikes, and didn't chafe at all under the packs. Had I done any of these activities in a cotton t-shirt, I know I would have been quite wet with sweat, given the conditions. The shirt has been washed 3 times now using All liquid detergent (the "free and clear"-type formulation) in a front-load washer on delicate, and dried in a dryer on delicate. While it's still early in its useful life after the 10 mile ride and about 12 miles of trail hiking, it shows no sign of pilling or other wear. To top it all off, my wife and I both really like the deep blue color.
Con: This is pretty minor, but each time I put it on, it is a tiny bit itchy at first. The sensation goes away after a little while (maybe 5-10 minutes after putting it on). I'm not sure if this is because I become acclimated to it or if I'm mentally otherwise occupied.
I'm about 5-9, 180 lbs, and have the large size. I could probably lose or gain about 10-15 lbs, and the shirt would still be a good size for me.
Prairie DogReceived free product
Chicago area
11 people found this review helpful
Most Helpful Critical Review
Not acceptable …
radbay3 years ago
I bought this shirt in black with high hopes that it would be on par with icebreaker products I had purchased before. I tried it on at the store and it fit well, but after washing it once the collar it’s so ragged, that don’t know whether I will be able to wear it moving forward. And perhaps even more disappointing is that when I wrote an email to customer service explaining the poor quality, I got a response saying “you can return it.” I know I can return it but that really isn’t the point. The point is we all expect REI to deliver quality products and quality customer service and on this occasion I received neither.
radbay
Atlanta
21 people found this review helpful
Customer Images
Lady in Pink
Yay-area, Cali
Yup, the merino movement is REAL!
1 year ago
I've been reading about Merino wool for years, but the price and mixed reviews of "it's itchy", "it's the best" has been keeping me away. Well, the price was right and the color (teal?) I took this to a Las Vegas weekend which is the perfect test. Used it as my undershirt while hitting the casinos, eating, pretty much the weekend part of on the Strip. Kept me warm while walking the Strip, kept me cool indoors. This was thick enough I wasn't "poking" thru the chest area (get it?) Size (XXL) I'm a big guy so it was loose or tight where I needed it. The smoke smell is still in it, hoping to hand wash to see how easy it is to dry.
Height:6'0"
Age:45–54
Weight:225–250 lbs.
Yes , I recommend this product
BRIVERS
Received free product
Lee Vining, CA
Solid Shirt!
4 years ago
The highest praise I can this is how unremarkable this is. I've worn this underneath a jacket on cool evenings, and as an undershirt in mid 90s temps. It's soft, but not the softest merino I've worn. Sweat dries very quick. The fit is perfect. It wraps the body closely, but is never constricting. It disappears on my body when I'm wearing it. There's nothing unbelievable amazing about, it does exactly what I want it to. It fits great, dries quick and is wearable in cool and hot weather.
Age:35–44
Weight:200–225 lbs.
Height:5'7"
Yes , I recommend this product
radbay
Atlanta
Not acceptable …
3 years ago
I bought this shirt in black with high hopes that it would be on par with icebreaker products I had purchased before. I tried it on at the store and it fit well, but after washing it once the collar it’s so ragged, that don’t know whether I will be able to wear it moving forward. And perhaps even more disappointing is that when I wrote an email to customer service explaining the poor quality, I got a response saying “you can return it.” I know I can return it but that really isn’t the point. The point is we all expect REI to deliver quality products and quality customer service and on this occasion I received neither.
Height:6'0"
Age:35–44
Weight:150–175 lbs.
No, I do not recommend this product
Reid
Michigan
Comfortable & heavy fabric. Perfect fit.
1 year ago
For a 100% merino (or near 100%?) it's pretty darn comfortable right away. This is a fairly heavy shirt so I don't expect I'll ever wear it in the 80s or 90s, but it's great in slightly cooler temps (60s-70s depending on sun, wind, etc.) and great as a base layer in the 40s and 50s. There is a slight itchiness when you first wear it, but it's less than other merino shirts I've tried, and as usual, it's getting more comfortable as I wear it more and wash it more. I got it on sale, and I'm suspicious that it's a bit overpriced at base price -- I don't think I'll ever pay full price for another one of these or any other $70-ish merino t-shirt. Also, the fit is basically perfect for me.
Age:25–34
Weight:175–200 lbs.
Height:6'2"
Yes , I recommend this product
MattT
Nice, kind of short
3 years ago
Based on the REI size chart I ordered an XL, even though in most brands I usually wear an XXL. REI size chart is accurate, as the XL fits me well around the shoulders and the middle. But for a "base layer" the XL is kind of short. I doubt it will stay tucked, and as base layers riding up your backjunderneath mid/outer layers is a PITA, I am going to return/exchange. I'm 6'3", so YMMV. The Merino also has a very slightly coarser feel than the similar name-brand product - at least when new and unwashed. But this is still nice and seems well made overall.
Height:6'3"
Age:55–64
Weight:225–250 lbs.
Yes , I recommend this product
RDP
Poor quality control
1 year ago
Lovely shirt, except there was a 2 cm wide hole in the back we didn't notice 'till aI wore it out. My biggest issue is partially with myself. I set the shirt aside and then forgot to return it until yesterday. When I brought it to the store they refused to take it - it's been 13 months. I understand that there is a twelve month (generous) return policy, but I feel that when you make shoddy merchandise you should stand behind it no matter how long it's been. Particularly when you charged $42 (on sale!) for a T-shirt. Very disappointed it REI's quality control as well as their store staff's bureaucratic adherence to policies.
TrailFly
Received free product
Los angeles, Ca
Soft and Comfortable
4 years ago
Got this in a L, for reference I am 5'10 / 175. It fits a lil loose like I like. Drapes plenty below the waist so its easy to tuck in or just leave out. Even though its summer time in California, when Ii wore it, the wool didn't soak, and it dried quickly. What helps is that is a thinner wool which works well. It would most like still make a good base layer in cold winter months. washed per instructions.. no shrinage and dries with no or very little wrinkles
Age:25–34
Weight:175–200 lbs.
Height:5'10"
Yes , I recommend this product
Prairie Dog
Received free product
Chicago area
Light, breathable, no chafing, good color
4 years ago
I'm pretty impressed with this base layer top. In the first two weeks I had it, I took it on three excursions: a c. 10-mile bike ride and two hikes. On the ride, it was about 75 with high humidity. Roughly 4 miles into the ride, it started raining and I had to put on my rain jacket. The jacket went over both my shirt and my backpack, so I worried that I would get very wet from the inside despite the pit zips in my jacket. While I did get a bit wet, I was notably drier than I anticipated. On the two hikes - one in a nearby forest preserve in the mid-80s and high humidity with no breeze (let's hear it for summer in Chicago) and the other in high 80s with high humidity and a fair breeze (Black Hills, starting at about 6200 feet of elevation and going up to about 6600), I had a 40 L backpack, and carried about 20 lbs of gear for the family and a couple liters of water. Pros: It's breathable, kept fairly dry during each of the hikes, and didn't chafe at all under the packs. Had I done any of these activities in a cotton t-shirt, I know I would have been quite wet with sweat, given the conditions. The shirt has been washed 3 times now using All liquid detergent (the "free and clear"-type formulation) in a front-load washer on delicate, and dried in a dryer on delicate. While it's still early in its useful life after the 10 mile ride and about 12 miles of trail hiking, it shows no sign of pilling or other wear. To top it all off, my wife and I both really like the deep blue color. Con: This is pretty minor, but each time I put it on, it is a tiny bit itchy at first. The sensation goes away after a little while (maybe 5-10 minutes after putting it on). I'm not sure if this is because I become acclimated to it or if I'm mentally otherwise occupied. I'm about 5-9, 180 lbs, and have the large size. I could probably lose or gain about 10-15 lbs, and the shirt would still be a good size for me.
Age:45–54
Weight:175–200 lbs.
Height:5'9"
Yes , I recommend this product
jakebrake
Michigan
quality and comfort at decent price
2 years ago
I own a couple of smartwool tshirt and these are just slightly thinker but 100% wool so unlike SW they don’t stick at all when sweating. I have been drenched in Michigan 90° 90% humidity weather and these shirts still feel like they move with you. Tighter fitting and do not become saggy even after wearing all day.
Height:5'10"
Age:35–44
Weight:200–225 lbs.
Yes , I recommend this product
Wrangler13
Received free product
Raleigh, NC
Great Base Layer
4 years ago
Just as the title says, great mid-range base layer. The merino is a bit thick for summer activities and a blistering sun, but makes a great base for early start hikes. Fits is a little baggy but has room around the shoulders and length for physical activities. Avoid climbing as chalk soaks right up by the wool and the weave doesn’t appear super durable for those occasional bumps along rock or walls.
Age:25–34
Weight:150–175 lbs.
Height:5'8"
Yes , I recommend this product
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