These lightweight RedHEAT ACTIVE men's base layer bottoms live up to their name with optimal body temperature regulation. The innovative fabric of these thermal long johns incorporates carbon microcrystals that store body heat, while its microporous structure maintains breathability for maximum comfort. The RedHEAT superior moisture management of Kombi's full-length base layer pants keeps you dry during high-intensity activities such as skiing or alpine touring. Plus, with a soft waistband elastic, a gusset for mobility and comfort, and anti-friction flatlock seams, you can wear them all day, every day.