The defeet un d shurt tank features a unique polarity of acrylics that draws moisture away rapidly made with microsupreme acrylic fibre this base layer is incredibly soft and comfortable to the skin the defeet tank is slightly thicker than the un d lite but still very thin un d shurt works well for layering even in warm climates in cooler temperatures just layer on another un d shurt or an un d flector works wonders for cycling running and winter sports defeet un d shurt tank features