Details: SMART ELECTRIC THERMAL UNDERWEAR SET: Men's plus size heated thermal underwear set, heat in a large area, 28 carbon fiber heating zones, insulated heating underwear use carbon fiber heating technology , temperature controllable. USB CHARGE: The electric thermals underwear base layer with soft fleece lined uses a USB interface.Powered by any 5V / 2A USB portable charger, the USB plug is compatible with most portable chargers on the market.Which can start heating in 30 seconds, long duration and long heating time.NOTE: NO POWER BANK ! TEMPERATURE CONTROL: 3-level adjustable temperature with indicator light to adjust the required temperature.Safety insulation design, built-in thermal protection module, 5V safety voltage, once overheated, it will stop running until the heat returns to the standard temperature. WASHING INSTRUCTIONS: Machine washable/hand wash. If the winter electric heating skiing underwear set is machine wash, please put the men's athletic base layers into the laundry bag to wash. To ensure the service life of the clothes, try to avoid strong washing and dry normally. Rinse it with clean water after washing.Do not wring it out. Hang dry it naturally.