One piece can fit around your stomach and buttocks where you are concerned about getting cold. Cotton silk blend pants with flanges that are soft to the touch and can be used to protect you from the cold all year round. It's just the right thickness so it doesn't show through your outerwear, and WHOLEGARMENT(R)'s flat knit fabric feels gentle on the skin. The width of the ribs on the hemline part has been changed to create a comfortable fit.