Made of airtight material, so be sure to use with your head sticking out. Risk of suffocation/ If water droplets form inside and freeze or the product is rubbed together for an extended period of time, the surface may become easy to tear, and the aluminum foil may come off in powder form.Children must be supervised by a guardian when using the product.Do not damage the product with pointed objects.Keep away from fire and other sources of heat.Do not use this product for purposes other than its intended purposes.