Breathable and warm, perfect under layer for frigid days! Most of my under layer leggings are not nearly warm enough, these fit the bill!

5'6' 140lbs S would fit snug, M would be comfortable, but I like it really loose so I bought Large. So lightweight and really warm. I wear them as pyjamas with a linen cami top. So comfortable I am hoping I can wear them year round, they might be a little warm in the summer but we shall see. I bought the blue and probably should have a second ...

I bought this to go with my reactiv lite grid top, but it's not as comfortable. Something about the fit and stretch is a little off for my body type. I have something similar from Black Diamond that fits and feels much better. It still does a great job keeping me warm on the slopes.