Firmly warms. Micoles unique technology for heat control The suitable temperature lasts for 9 hours. Wide toe shape for a secure fit. The toes are sure to keep you warm. Thin and does not slide around. Thin and fits perfectly under the shoe, so it wont slip even when walking. ● Comfortable to use with less discomfort. Maximum Temperature: 104°F (43°C); Average Temperature: 99°F (36°C); Lasting Time: 9 hours (measured value intended for use in shoes) The displayed temperature and time are measured for use in shoes. There may be slight differences depending on your usage environment (temperature, shoe type, etc.). This product is manufactured in an ISO9001 certified factory that is international standards for quality assurance. Japan Chiro Industrial Member: