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  • Icebreaker BodyfitZONE™ construction combines lightweight 200g stretch merino wool with strategically placed merino mesh panels for ventilation
  • Gusseted side panels for ease of movement
  • Flatlock stitching keeps these bottoms from chafing during long days of dynamic motion
  • Corespun fabric for enhanced durability


View all Icebreaker Men's Long Underwear Bottoms

REI membership


Best Use Snowsports
Fabric 96% merino wool/4% Lycra spandex
Moisture Wicking Yes
Quick Drying Yes
Underwear Weight Lightweight
Inseam (in.) Unavailable
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 4 out of 5 by from Prime fit, exactly what I expected For running I was tired of synthetic materials for my base layers, mainly because of smell, improper fits so I looked into Icebreaker because I have a few shirts I really like so I was looking for something in this department, something that was longer, like these that almost come to your knee, I bought a medium, very comfortable length, I'm 175, 5' 11", would like to be 165 if you know what I mean. They fit comfortably everywhere, good tension fit but not riding up, I have high expectations and I'm thankful these lived up to it. I use them running, hiking, outdoor work, and basic wintertime daily use. Good job Icebreaker.
Date published: 2015-11-13
Rated 5 out of 5 by from Perfect length Wore these to yoga twice so far & they are very good. The length is great & don't roll up during poses. No need to wear another pair of shorts over these. They are thick enough & have no fly. Bought two pairs. I'll also wear these under my jeans instead of long Johns. I really only need coverage to the knee & the weight is perfect. Thx. For not putting a fly on these making them truly multifunction & not just underwear.
Date published: 2015-12-08
Rated 5 out of 5 by from Just what I was looking for... I wanted something for cool mornings that I could wear under my shorts without it coming past the knees. These feel great against the skin. They do just what I want them to do.
Date published: 2016-01-02
Rated 5 out of 5 by from zone shorts keep you in the zone great product, allows you to focus on activity (yoga, hiking, running, b-ball) while maintaining good comfort and temperature. much appreciated.
Date published: 2016-08-15
Rated 5 out of 5 by from Very Comfortable and Warm I have used these under cargo shorts in multi-day hikes in the high 50s F down to the high 40s F and was surprisingly warm and comfortable and not stinky. I have also run in them under thin running shorts with no liner and found them to keep me warm down to the low 40s F and still comfortable yet sweaty in the high 60s F. The also work well as underwear when you need a little extra warm but do not want to wear long underwear.
Date published: 2017-02-28
Rated 4 out of 5 by from Under layer I already had a pair and wanted to get more before they no longer existed. Not as comfortable as another pair I had from another company but, they'll do. They o dig into the butt crack some so, you may need a pair of underwear for them to be more comfortable. They're used in place of a pair of long underwear pant when I wear my lined pants.
Date published: 2017-02-21
Rated 5 out of 5 by from Shorts keep a 68 year old Coumadin patient warm I'm comfortable wearing these Bodyfitzone shorts under hiking shorts at 40 degrees F. I may be able wear shorts into the 30's when my Icebreaker knee high compression socks arrive.
Date published: 2016-12-22
Rated 5 out of 5 by from Shorts are used for yoga I use these for yoga and they are great. Very comfortable and also great fit.
Date published: 2015-11-17
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