Though its predecessor was damn near perfect, Assos was still able to tease some improvements out of the latest LS. skinFoilwinters7 Body Insulator base layer. While the base material remains largely unchanged, a few alterations to certain areas of the base layer make for more comfort and less bulk. The neck, for instance, is now a softer material with better stretch and return qualities so no zipper is necessary. The seamless design of the torso is also stretchy enough to slip on easily, adapt to different body shapes, and move without restriction.