Think breathable space blanket. This proprietary, thermal-reflective insulating system from Columbia is up to 20% warmer than  other traditional. Select Columbia products have 35% of their liner surface covered in tiny, reflective dots that reflect body heat generated by the wearer. Essentially this system allows the user to help generate their own warmth. The remaining material is an ultra-breathable, moisture-wicking material that helps disperse moisture and any excess heat. Look for this lining in Columbia coats, pants, and even gloves.