YakTrax Thermal Insole -Keep your feet extra warm while out in the cold weather with the Thermal Insole from Yaktrax! One Size Fits Most/ Trim to Fit Heat Rated to -13 F Blended Polar Felt Made From Woolen Fibers Radiantex Mylar Coated Polyfiber Moisture Repelling Hand Wash/Air Dry Style: 8309