Thermal leggings are a type of clothing designed to keep you warm in cold weather. They are made from a material that helps to insulate your body and retain heat. Thermal leggings are often worn as a layer under other clothing, such as pants or shorts, to provide additional warmth. They can be a good choice for outdoor activities such as hiking, skiing, or snowboarding, or for staying warm while working or exercising in cold weather. Some thermal leggings are designed to be moisture-wicking, which means they can help to keep you dry and comfortable by pulling sweat away from your skin. They may also have features like flat seams or stretchy fabric to increase comfort and mobility.