This revolutionary functional vest uses evaporation to cool riders. When the vest is wet or damp, the HyperKewl system locks in the moisture and stores it for up to eight hours, providing a 6 to 12 °F temperature reduction for the wearer. · A cooling vest with HyperKewl functional fabric at the front and back · Constant cooling effect through evaporation · Outer material: nylon and polyester functional fiber ·Stretchy side sections made of mesh ·Front zip · Color: Grey · Sizes: Unisex XS-4XL