Patagonia  Capilene Thermal Weight Long-Underwear Bottoms - Men's

I'm rather thrifty with gear, but when it comes to warmth, I have decided after much trial and error and miserable frostbitten events, I will splurge on the right stuff. I tend to run to cold and have a hard time warming up, but this base layer kept me toasty. (almost too toasty when active), but comfortable after sundown and sitting around camp during a recent winter camping experience. The nights probably dipped to 20 degrees while we are standing around camp ( i had this layer, one other 100% polyester warm up pants, and then insulated burton snow pants and nothing was cold with the exception of only my fingers and toes. I am unsure what to compare this to as my old set up was all wrong, but they are great if price is not an issue for you. 5 star performance 4 stars for price.... cmon patagonia.

I usually wear merino baselayers, but after several of them developed holes in them, I decided to try these poly pants instead. I find the sizing of these really odd. Usually with baselayers you want a skin tight fit. But these are pretty loose. And really long too. I wear medium in most North American brands, including Patagonia. And I bought a medium pair of these pants. The pant leg goes all the way down, around my ankle, to cover half my foot. I would definitely recommend sizing down if you are thinking about getting a pair. Warmth wise I am not so sure, as I haven't tried them in the cold yet. But just trying them on at home is making me wonder if I should keep or return these.

I have mixed feelings about the thermal weight Capilene. The material is ribbed - not uniform in thickness. This makes the fabric really breathable and light but I’m not sure it’s the best for static cold weather activities. I’ve used it mountain biking in 20F weather with only nylon pants on top and warmth and moisture were both non-issues. I really like these - I just find the price to be a bit steep - even for Patagonia

I would call this a mid-weight base layer. It is not as thick and warm as Patagonia's older thermal weight long johns. I'm slender, and even so it was too tight on my thighs and calves. For this price, I expected a much more beefy layer.

I went back country skiing in Teton Valley, Idaho (more specifically the palisades and I would ski in only these and a shell and would be so comfortable. Definitely recommend to anyone looking for warmth and lightweight underlayers.

From a materials perspective these are a best-in-class base layer. Excellent warmth/weight ratio and breathability. But the fit is very weird. I am a consistent size Medium in all the outdoor gear and clothing I own, including every other Patagonia piece I use; I bought these in Medium and they are very loose and baggy. The waistband fits perfectly, but everything from the hips to ankles fits like a Large. This really affects performance, especially for active movement — there’s just a lot of extra fabric, and the loose fit doesn’t help with moisture transport or thermal efficiency. I have an older pair of these in size Medium, and they fit perfectly, so I suspect Patagonia repatterned these recently. Will try a size Small (which is a little crazy for a lean 6’ and 180lb guy), but I suspect that they will be too tight in the waist.

Needed comfortable base layer for late season hunting and needed base-layer to wick away moisture during high activity like skiing-these fit both criteria! Very comfortable, size spot on.

I found the construction to be a very thin, see-through type mesh fabric, with stripes of felt-like insulation. The stripes were about one-quarter inch wide, and in between each insulating stripe was about one-quarter inch wide stripe of mesh fabric. Insulating ability of this fabric is not very good. They would work for light layers on a moderately cool fall day, but it’s not good enough for actual cold weather, like temps in the 40’s or lower.

wore these while duck hunting and perfectly comfortable

Arrived this cold PNW afternoon and I haven't taken them off yet. :) Warm soft fabric and a wide and stable waistband, very comfortable. Size note: I'm male 5'10" with a 32" inseam and a 36" waist. I bought MED because I wanted a snug fit inside of fishing waders and cycling rainpants. The medium fits perfectly, waist snug but comfy and legs tuck neatly into my socks.