Yaktrax Thermal Insoles provide an easy and effective solution for people with cold feet. With a Radiantex layer that reflects warmth back to your feet and polar felt to trap the heat, these insoles are sure to keep your feet toasty. . Radiantex layer redirects heat back to feet and keeps moisture out. Blended polar felt traps in heat. Sold as one size, trim to fit. Heat rated to -13??F 96506083098 27193700018 8309