Heat Factory Foot Warmer Insoles (7hr)

Heat Factory Warmer Insoles are designed to be worn with socks inside shoes, boots and other air-restricting footwear. Heat Factory's Foot Warmer Insoles provide up to 6 hours of reliable, even heat. The Foot Warmer features an adhesive backing that adheres to the bottom of your sock, allowing it to stay in place when walking, biking, hiking, skiing and other activities. The Insole foot warmer has an ultra-thin design for comfort and measures the full length of an average insole to ensure your entire foot stays warm. The Heated Insole is designed for restricted air environments and therefore is not intended for use in open air.