This top is very light, but as far as warmth it is definitely just right for a mid-weight. The inside of this is super soft and comfy. Blocks wind like a brick wall yet doesn't feel too hot. My only complaint is the sizing. I have other Marmot tops and the mediums fit just as I want them to (5'11, 175 lbs) but this medium fits like a generous large.

Absolutely love this base layer. Not only is it plenty warm when combined with a lightweight fleece and shell on colder days, but it wicks away moisture very well and keeps you dry when sweating hard on a long tour in warm weather. I'm 5'10" & 215lbs and felt the XL fit true to size, however, the area around the neck is a bit looser than I would like. Sleeve length seemed to be perfect.

Great midweight baselayer. Not the most "stink proof" shirt I've ever owned, but it's pretty decent. Wore it alone for a week in the Smokies with a light fleece and Columbia shell with temps in the 30's and I was plenty worn. We'll see how good it breathes this summer once it warms up a bit.

I have the zip-T version of this shirt and it seems I hardly take it off. I wore it for a 40 mile backpacking trip, washing it in streams, I wear it around town, and it is a great night shirt worn to bed. Though it is a synthetic fabric it feels more like wool and has that fuzziness feel to it.

Overpriced like a lot of "technical" stuff, but this is the kind of thing you pick up on sale. I've never been let down by anything made by Marmot, and I hardly understand why this brand isn't ballyhooed about more often.

Great fit, great material, great all around. Plan on this doing the trick when your out in the cold. Marmot has the best fit and feel of all the baselayers in my opinion.

I really wasn't sure about the color of this shirt and still aren't, but it fits perfectly and boy is it toasty! I'm definitely keeping it! It's not too form fitting, but doesn't bunch up if you wear other layers over it.

this is the best long underwear i've ever owned. extremely light but warm. wicks sweat away extremely well. wore them 3 days straight and no smell at all. going to get more. order your true size. got a med. and it's a tad short

Bought this for my Dad. He is in his 70's and does not understand great gear. I have made him a believer. Super soft. Nice and warm.

came in the mail and i put it on, until a week later when my girlfriend made me take it off because she was bored of looking at it. somewhere between light and medium, feels like a long-sleeved t-shirt, keeps cool and warm. recommended.

Own several pieces of marmot gear and have consistently been size large, which is consistent with their sizing charts. The large of this piece is fairly loose compared to other bits of gear so consider sizing down if want a trim fit. Been great so far, planning to give it more rigourous testing in a couple of weeks with a winter trip to alpine regions

This shirt was great! Wore it for four straight days hitting the mountains in Utah hard and it was warms as could be and it didn't smell in the least!