These are my go to long underwear for anything cold. If really cold I add a Cloudveil Run Don't Walk Tight, but only if it is REALLY cold and I am using Schoeller type pants vs. hard shell. If in a hardshell then these are usually warm enough. They fit well. I wear a large and have a 33" waist and 32" inseam. I use them often and they are holding up well. Super comfortable against the skin. Don't smell. Good fly. Elastic waist band holding up nicely.

Highly recommend this product.

I have a handful of Icebreaker tops and love them all so I decided to pick up a pair of bottoms as well. I find the Icebreaker generally runs a bit small, even when I size up they are fairly skin tight. Unfortunately, I thought I'd try my recommended size with these guys and they ended up tighter than I would prefer. On the plus side, the merino wool is very soft and has exceptional breathability. Bottom line: If you don't have skinny twig legs, or don't want your baselayer to fit like spandex, think about sizing up!

I've been using these for two years now, for both skiing and for some cold weather backpacking. These are a very comfortable baselayer that has a good fit and the fly is a definite plus for me. The pants appear to be well made, and they wash well in a washing machine. I have two complaints - the first is that they appear to be stretching in the second year of use. Not to the point that they aren't usable - they still have a snug fit - but it is obvious that they are no longer returning to their original shape. Second - I have a pair of REI MTS merino wool pants that I got for a fraction of these that are every bit as soft, comfortable and good-fitting, and the REI leggings haven't stretched. REI doesn't appear to be making these any longer (very disappointing - they were a great deal), but this is one of the rare cases where I found Icebreaker to be second place to another brand.

I love these bottoms. I used them for hiking/packing or even hunting. The 200 weight is great for active pursuits in cold temps or more stagnant hobbies with cool temps. They couldn't be more comfortable.

Sizing: A lot of people have mentioned that they run a size small, but I'd disagree. I'm 6' and a lean 200, and they fit nice a snug. These aren't meant to be pants, they're a long UNDERWEAR. They're supposed to be skin-tight, but not constrictive, to go underneath everything else. They're bomber and I'd recommend them to anyone.

Have only worn a few times but the large fits well and a little tighter than my Smartwool leggings which I also bought. I'll wear these for running instead of tights or under more fitted pants.

These pants are great and Icebreaker puts out great products. These pants keep me warm, do not itch, wick sweat, and they fit snug. I do not prefer a bulky base layer and the next to the skin fit is perfect for me. There is much room to flex and move as needed. All around good product. I'll be buying another pair probably.

Merino wool is superior to synthetics for warmth and wicking. Breathe extremely well and fit great. Control odor after days of use.

I loved the 200 tops, so I got these and ditched all my other bottom baselayers. I'm 5'8, 150 and the mediums fit perfectly.

got them for my husband who usually tends to be too hot going down no matter what he wears. but this ones zap mosture perfectly and can be worn over and over, well to a limit

huge Icebreaker fan to begin with - own several tops. these were my first bottoms. just warm enough to ski all day long, thought when i first received them they might be too thin but after wearing 10 days skiing in varying conditions haven't got a complaint so far. hope u like that skin tight look!

Lightweight, breathable. Great for all but hot weather. DOESN'T retain odor, even after many days of use.

I have the old version with no fly but these are some of the best base layer I own. I wear them everyday under my suit and around town, because it gets well in to the negative teens with the wind chill here. my legs are never cold. These guys move well with my body and unlike some synthetic pairs I have, I never feel these bunching up or pulling.
I have a 36" waist and I sized up to an XL because I like a little room. and they fit great.

They are not "sexy" to wear by any means but they seem to work well. I give them a 5 because I have no complaints. They are a bit baggy in the crotchial area.

Just used it in 5-10 degrees snowshoeing with just light wind pants. Plenty warm enough and though I sweated I never felt wet, clammy, or cold. Definitely 'Love it'.

Consider the sizing to be European, but not as small as Italian. They run maybe a half size smaller than American.
A quality product.

I love this product! They're thick enough to keep me warm, but thin enough to breathe well. I'm 6'2" and 180 lbs, I like the XL, they're a bit baggy, but I like them that way.

As usual, icebreaker kills it with the body fit leggings. I have the women's and got these for my dad for the holidays and he is loving it. They are the warmest and thin enough to wear even if you just want to put them under jeans. You can sweat in them while skiing for days and days and they still won't smell!

This is the best base layer I've ever owned. The Merino wool is very comfortable, warm and dry. I'm a bigger guy and the XL size fits me perfectly. I highly recommend these to anyone who's going to be outside in cool temps for any period of time.

Silk beats this junk by a mile.