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  • Soft, nonirritating merino wool offers lightweight warmth next to skin and resists odors naturally
  • Merino wool wicks away moisture, dries quickly and breathes to regulate temperature for outstanding warmth in cold weather
  • Fabric offers protection from UV light with a rating of UPF 50+
  • Flatlock seams reduce chafing, offset shoulder seams will not rub under backpack straps and side seams wrap toward the back to prevent hipbelt chafing
  • Extended hem increases coverage
  • Machine washable; line dry or dry flat in shade
  • The men's Icebreaker Bodyfit 200 Oasis crew long underwear top has a slim fit


View all Icebreaker Men's Long Underwear Tops

REI membership


Best Use Multisport
Shirt Style Crew
Fabric Merino wool
Sun-Protective Fabric Yes
UPF Rating 50
Moisture Wicking Yes
Quick Drying Yes
Underwear Weight Lightweight
Sleeve Length Long Sleeve
Gender Men's

Size chart

Sizing notes

Measurements are stated in inches unless otherwise indicated. CHOOSING THE RIGHT SIZE: If your body measurements are midway between two sizes, select the smaller size for a tighter fit or the larger size for a looser fit. If your body measurements result in different sizes, we recommend using your chest measurement for tops and your hip measurement for pants.

Rated 5 out of 5 by from An essential top for all seasons. Go and buy it!!! I've had this long sleeve top for almost a year, and i simply love it. From day one, it's been one of my go to tops. I've worn it last winter, spring and even in the summer. It's feels so soft and cozy to the skin that I even wear it to sleep. It's great to wear under any shirt or sweater, particularly on those cold days. I highly recommend it to anyone looking for a dependable, breathable, comfortable and high quality top/base layer. It may be a bit on the pricey end, BUT I gotta say it's well worth the money. Please go out and buy it!!!
Date published: 2013-01-21
Rated 5 out of 5 by from Versatility At Its Best I have used lots of Icebreaker items in various conditions and this has certainly proven to be the most versatile piece IB has to offer. As for the basics: it breathes incredibly well, can be worn multiple times out without building up an odor, dries fairly quickly, and does not itch. To add to this, it can be used in temperatures ranging from warm to freezing. Once I get active and moving in this top, I have used it alone in temperatures ranging from 30-35 deg. F, even when it is lightly raining or sleeting on and off; just this top has kept me plenty warm while breathing well, to the point where I haven't even had to put gloves on because my hands are just as warm. In addition, as you may have guessed, it still insulates when wet, and if sweat or rain builds up, it simply beads up on the shirt (not soaking in like cotton) and you can flake it off, almost like a natural DWR. Conversely if it gets really warm, to the point where I can't sleep at night, I can also just throw on this top and somehow it cools me down slightly to the point where it feels comfortable; how it does this, I have no idea. But you can use this top for any weather variations in between as well. Just keep in mind, if it's cool and windy, I would get a shell to go over it because the wind can get through it. Also, in terms of sizing, it is a tight Bodyfit so if you are in between sizes, you may want to size up unless you like it really tight. But just follow the care instructions and the top will be as good as new for a while. If you can't already tell, I highly recommend this piece!
Date published: 2012-06-22
Rated 5 out of 5 by from Perfect for everyday wear Great weight for everyday outerwear. They could leave the Icebreaker name and logo off the sleeve of the garment and enhance the places it could be worn.
Date published: 2015-06-07
Rated 3 out of 5 by from Different fit This review is for the 2014 Oasis crew base layer. After completely wearing out 3 body fit Mondo baselayers, it was time to replace them. Unfortunately for me the arm length on the new Oasis is about 1-2 inches too short and not tight enough. I'm 6'2" 180 athletic and have been a large size in this garment. The XL would've been too big overall. The gusseting seams are better in the previous version IMHO too, but that's not a deal breaker like the arm length. Overall quality is good like we've come to appreciate from Icebreaker. Bring back the Mondo Zip please!
Date published: 2014-03-19
Rated 5 out of 5 by from Best Merino L/S Crewe The best merino wool undershirt. The Small fits me perfect. Form fitting under shirt. Perfect for layering during colder months with the Pursuit or the Cross Cut and solo during warmer months. Bought several of these in different colors. Bottom line you can't go wrong with your investment in this product. Icebreaker makes excellent quality products and this is one of them without question. Go and buy and you will not regret. Worth your investment and it will last for a long time if you take care instructions during washing.
Date published: 2013-04-30
Rated 4 out of 5 by from Great vest but why no white? I have had several Icebreaker Bodyfit long sleeve vests, in 200 and 260 gms and love them. They are not cheap but do everything that's claimed. I especially like the fact I can wear one over several days and no matter how sweaty things get it doesn't retain odour, unlike similar, albeit cheaper, vests from competitors. My only gripe - and why I don't give them five stars - is they come in such a limited range of colours - and no white! I'd take off-white or skin tone, even light grey if they were available here in Australia. I have now ordered a grey (Monsoon) from a NZ supplier online. My only other comment: they come with a stuck-on label inside the neck. In some shirts (not Icebreaker) I've found these can go brittle in time and can irritate, so I prefer labels I can cut off or unpick. So far, though, the labels on my oldest Icebreakers have caused no problems. Overall, I'll keep buying them for everyday winter wear - just improve the range of colours, please.
Date published: 2013-07-05
Rated 2 out of 5 by from Bitterly disappointed I had read lots of reviews about this product and bought one hoping that it would become an essential part of my camping equipment. I found it incredibly itchy against my skin and deeply uncomfortable when worn with a rucksack. Around the upper back and shoulders was especially unpleasant. In the end I could not where it for anymore than an hour before replacing it with an ancient synthetic t shirt which cost me pennies years ago. I was really hoping that this garment would be something I could wear for a week comfortably, in the end I lasted 4 hours maximum before feeling discomfort. What rubs salt into the wounds is the high price. I suggest that you try one of these on before purchasing.
Date published: 2012-08-21
Rated 4 out of 5 by from Versatile Piece The Oasis Long Sleeve Crewe is a versatile piece that can be worn for lounging around the house in the colder winter months but can also be worn running errands or working in the yard. It's very warm and I love the navy color. A medium in the Tech T fits me perfectly, so I ordered a medium in the Oasis LS Crew as well. However, the fit is slightly smaller. This probably has to do with the fact that it's a heavier weight, but it's still something to consider when ordering. My only real complaint is the logo on the left upper sleeve. I would have preferred the stitched logo on the chest, as seen in the Tech T.
Date published: 2016-12-06
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