great bottom
It is a Great pair of leggings, very comfy and warm when the temperatures hit way below 0C. Fabric is breathable, it is suitable for running I like this bottom. so recommend you buy.

Very warm baselayer, Without any doubt, it 's the warmest baselayer I owned, moreover, it 's so breathable and light, I feel so comfy with it in last winter, of course, It has a high quality. I like it!

Womens RHO AR Bottom
I liked these so much that I have an extra pair so I have a clean pair for Sat. & Sun. I am always outside 0n the weekends either on the bike trails or sledding or hiking, skating etc. They are comfortable, warm, and keep me dry. The are not too hot to wear in the fall and early spring weather either. They fit just right and they fit comfortably inside my boats without being bulky. I don't think twice about wearing them into the store or a place to eat. They look sporty without looking like long underwear. The zipper pocket on the leg is in a great spot. I wish they came in brown and navy or dark green colors also.

FUNCTIONAL AND AWESOME!!
If I had to describe the Arc'teryx Rho AR bottom in one word it would be: AWESOME! These bottoms are incredibly warm and soft! They are great alone or under gore-tex pants without feeling too bulky. These tights will keep you warm in extremely cold temperatures (so far they have kept me warm w/ a light gore-tex shell over them in 6 degree weather)! They are also great w/ wicking sweat off your body so you don't freeze!! I have also found that you can wear them multiple times without washing as they don't hold in an odor and don't have an icky dirty feeling to them. I also love wearing them around the house b/c they are super comfortable!! I am 5'1, 115lbs and the size small fits perfect (when I was 105 lbs the size small fit really well too). I have found that Arc'teryx is by far the best fitting brand for the petite woman! The quality of Arc'teryx products cannot be matched by any other brand...and trust me, I've tried them all! If you want warm, soft, great fitting pants then get these, you def won't be disappointed!!

It's warm and comfort
This underlayer is warm and comfort, breathable as well, I love it very much. Selcet arcteryx will never make you regret.