Who Makes The Best Thermal Underwear?
Who Makes The Best Thermal Underwear? Best Overall: Thermajane Thermal Underwear Set. Best Affordable Option: Amazon Essentials Thermal Long Underwear Set. Best Wool Option: Smartwool Merino 250 Wool Base Layer Top & Bottom. Best Silk Option: L.L.Bean Silk Pointelle Top & Bottom. What kind of thermal underwear is warmest? Merino wool is the best material