*Wicking layer: To keep the skin dry and clean by quick drying. It can quickly absorb our sweat and draw moisture away from the body. *Insulating layer: By isolating the inside air from the outside to retain the body heat from the cold. The thicker the layer of accumulated air, the better the effect of keeping warm. *Outer Shell: It is easy to clean and has the functions of deodorizing and antibacterial, moisture wicking, cool and breathable comfort.