The Yaktrax Thermal Cold Weather Insoles for Men and Women are ideal for keeping feet warm and dry when working or playing outside. Made from blended woolen polar felt and recycled blended felt, the fray-resistant boot and shoe inserts wick moisture while providing cushioning and insulation. A Radiantex thermal layer helps to redirect body heat to the feet, keeping them warm and dry when walking, hiking, or working in frigid weather; insoles are rated to -13 degrees Fahrenheit. The Yaktrax Thermal Cold Weather Insoles can be trimmed to fit men's and women's boots and shoes, ranging in size from a women's size 6 to a men's size 12.