very thin material. May not keep warm on really cold days, but a good thin layer if moving around a lot or if weather's not too cold.

I purchased these for my husband so that he can run without getting cold in the winter. They fit perfectly and he loves them!

It's the right thing to get for the comfort of silk at the price of an itchy cotton pair of thermal pants.

They were comfortable and kept me warm in 9 degree weather.