The Peak Performance Magic Long John Thermal Leggings are a highly functional first layer, ideal for all types of physical activity. Thanks to the combination of merino wool and durable polyester fibers, they are highly breathable, quick-drying, flexible, and warm. They are also exceptionally durable and soft to the touch. Furthermore, they feature flatlock seams that prevent irritation and chafing. The material is soft to the touch and completely non-irritating.