The ONLY base layer
I was a cap buyer for ages... I moved to wool for 10 years... and then this came along. I have flushed the fur from my baselayer lineup after just one day in this baselayer. The OmniHeat makes it regulate. the first day of use was a Fall run. It was 38F and overcast. I wore this top with a light shell and was just fine on a jog for 2 hours. It did not wet out nearly as quickly as the other pieces i have worn.
Skiing... I went cat skiing and spent some time hiking in the high alpine. People were going hot to cold, as they hiked then sat and waited their turn. I was one temp all day and the temps/conditions were all over the place that day.
It regulates and fits great. This is the first 5STAR i have given