The fabric is very warm. After I lost weight, I found this style very comfortable; it feels too tight if you're very curvy. It keeps me warm around the house, solo, or worn as a base layer out 'n about. I like loose clothing so I got the next larger size. The original set was purchased elsewhere but I bought a set of them here, today. This is a trusted source for winter clothing.
I remember my father using duofold products, so when I needed thermal underwear, I went in search of this brand. And I was not disappointed. Excellent quality, soft fabric, keeps me warm inside the house or walking the dog. Great for layering under sweats or jeans. Washes well.
This is a good base layer. Not as warm as I would have liked but I may be biased since I come from 90 degree weather. It is pretty good tho. I would recommend. It stays in place, is comfy and true to size
Unlike the expedition-weight Varitherms (see my review there), Duofold did not tighten the waist band of these one-layer tights, so they are still very comfortable. They are the best mid-weight performance tights at the best price of any brand. They are great for backpacking and running in colder weather, and for casual wear.