Stay warm this winter without bulky clothes, thanks to the best thermal shirts, from classic waffle knits to slim-fit ...

Thermal Knits (Waffle Knit or Ribbed Textures ... We didn't just pick any old thermal shirt off the shelf—we tested the best of the best like we were gearing up for an Arctic expedition.

Merino wool and wool blends are best suited to high-output activity ... Warmknit material is a throwback to classic waffle-knit thermal underwear, but with modern fabrics that boost comfort ...