Review on Stay Warm and Comfortable with Artic Pole Boys Thermal Underwear – Perfect Clothing for Active Boys by Charles Barney

used by grandson at scout camp nightly at single digit rates. He wore two pairs with a Boy Scout uniform over them. Only remove your uniform before climbing into your sleeping bag at night. Alongside teenage and 20's daywear with gusts of 25-35mph, he wore a jacket and then his double lined HEAVY coat. He was warm enough for the whole trip, so he was the least of his complaints! I'm not doing this underwear justice, the key was the multiple layers. Heat packs for legs and arms etc etc but they worked fine for sleeping in his zero temp sleeping bag. also had a zero degree tent.