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  • Polartec® Power Grid™ fabric has a smooth face for easy layering
  • Grid backing wicks away sweat, dries fast and traps warmth
  • Fabric is bluesign® approved with 66% recycled polyester content
  • Treated with Polygiene® permanent odor control
  • Brushed elastic waistband for next-to-skin softness
  • Gusseted crotch; functional fly
  • Chafe-free flatlock seams


View all Patagonia Men's Long Underwear Bottoms

REI membership


Best Use Multisport
Fabric 97% polyester (66% recycled)/3% spandex
Moisture Wicking Yes
Quick Drying Yes
Underwear Weight Midweight
Inseam (in.) Unavailable
Gender Men's

Size chart

Sizing notes

Inseam varies depending on style. Measurements are stated in inches unless otherwise indicated.

Rated 5 out of 5 by from Sizes run big, but it's a great pair of tights! Like others have said - sizes run a bit big. But otherwise I have no complaints. These keep me warm all day in so many situations. I opted for the midweight because I own a pair of thermalweight that I rarely use for very active days in the deep cold. These midweights are good for temps between 25-45 F, for me. I won't use the thermal layer until things get into the teens. They're light enough that I can wear them to work too and not overheat.
Date published: 2016-02-03
Rated 1 out of 5 by from Patagonia really needs to work on their QC This is my third pair of the newer Capilene pants. I wear size medium with a 32" weaist so I tried on was a size men's medium, it fitted me except the waistband was as if it was fitted for a size large and thus way too loose. The second had a problem with the thigh area, it was way too small and it had already ripped its seams along the inner thigh from someone else. Then I finally got my third pair, it fitted me good at the store, so I bought that pair. On my first outing, I noticed the waistband was becoming too loose and kept riding down. When I got home afterwords, the waistband had apparently stretched out, the elastic had failed. I still tried to wear them for a few more outings using my pant belt cinched tight enough to hold them up, it kind of worked. That is until I noticed the seams were ripping along the seat area and the fabric had runs alone the leg. This is from just from a total of 4 short outings and what I consider very light use. I have had them for less than one month. The older versions of the capilenes were awesome, I still have several pairs and after several outings and very heavy use, they still look new and feel great. I cannot recommend these, to anyone that plans on using the new capilene mid weight for actual backpacking, hiking, climbing, let alone search and rescue. Due to their poor quality control, poor durability, and poor design. Maybe the new capilene mid weights were meant for casual wear, I am not sure if they'd hold up for that.
Date published: 2016-01-16
Rated 5 out of 5 by from 100% awesome I haven't taken them off since I got them. I haven't been cold since I got them. My wife and coworkers are still interacting with me so that means they don't smell. Thanks guys!
Date published: 2016-01-09
Rated 5 out of 5 by from Great addition of equip. For yourself or a Gift! I'm an kinda an old guy (56), with years of experience, alot of cold activities. I wear these Float Tubing, Hiking, Skiing, Hunting, whatever. I got these as a gift from my son from the REI store in Westminster. I think these are remarkable! Their lightweight, comfortable, & even look pretty cool! (wife said it, haha) I dont wear anything under them so dont see the elastic stretching, I only wash them in gentle cycle, and air dry them either by hanging or in the dryer. (They wick moisture off so well they dry super fast). ( I seen some of the comments here & just had to throw my 2 cents in as well!) Great Product, Very reasonably priced! (You want good equipment then its a super small price to stay warm & comfortable). Tired of being cold, or want to give someone a great gift, then this is a fantastic price for top quality equipment. (Had them on in up to -50 w/ windchill & toasty warn still!)
Date published: 2016-12-14
Rated 3 out of 5 by from Patagonia med. base layer A good product overall. The sizing runs a little big and they fit loosely. Still kept me warm @ -8 degrees in Jackson Hole. Last week.
Date published: 2016-01-09
Rated 5 out of 5 by from Hubby loves it! A few years ago, I bought my husband a set of these. He had been using his old Army-issue wooly long underwear for years and was hoping for something more comfortable and updated for ice fishing. He loves them! I decided to buy him another set this past Christmas. On the very cold days, he has taken to putting on both sets before heading out to the lake. He stays warm but doesn't overheat, and doesn't feel restricted or bulky with all the layers.
Date published: 2017-01-11
Rated 2 out of 5 by from As usual, a good product at a high price Needed some base layer underwear for a trip to Chicago this April. These worked fine for our hail, snow and high wind trip. Could've used something a bit warmer but for this time of year every store had limited slow moving items left on their shelves. For the price, I don't think they are worth it when you can buy REI brand for almost half the cost.
Date published: 2016-04-14
Rated 5 out of 5 by from Kept me warm Being from sunny California I had to buy this Midweight Long underwear when my daughter wanted to visit the North Cascade Institute in January this year. These underwears kept me very comfortable and helped me enjoy my stay in the park.
Date published: 2017-01-21
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