KEEP YOUR FEET WARM: Self Heated foot insoles with even heat generation, quick heating, distribute heat evenly over the insole surface. No electricity, boiling or additional warming is necessary for the heat pads. ADVANCED HEATING SYSTEM: This warming sole uses titanium nanocrystal heating material with wash and flex resistance to form an advanced heating system. You can clean it with water for recycling purposes. SAFE AND RELIABLE: Winter Insoles, Energy-saving environmental protection, safe and energy-saving. The heated soles can be cleaned. Winter Insoles, Dry it before use. SOFT: The ultra-thin and comfortable warm insoles are barely noticeable and suitable for every shoe bed — no matter if it's a ski boot, a winter boot, or an elegant lady's shoe. BUY WITH CONFIDENCE: Washable and reusable. It can be washed directly without altering the use effect.