Description This is a pair of heated insoles. Rechargeable heating, to solve the winter foot frostbite. Make your foot more comfortable and warm. Adoption of premium material, this product is durable, handy and long-time use. Low power consumption and slight current, no great risk. Features -Color:Black.-Material:Plastic, carbon fiber, built-in battery.-Size(41-46): About30.00X9.50X2.00cm/11.79X3.73X0.79in. -Voltage: 3.0V-4.2V.-Battery capacity: 2100mAh.-Input: AC/100-240V40-60Hz.-Output: DC/4.2V-5V 500*2.-High temperature: 55 degrees, use time: 4 hours.-Medium temperature: 50 degrees, use time 6 hours.-Note:The color of the USB cable is in random.-The warm foot insole produces even heat and has a high heat conversion rate.- The heating is rapid, so that the heat is evenly distributed on the surface of the insole.- The heating bottom adopts high-quality and safe materials to form an advanced heating system.- The heated insole is non-slip, resistant to high temperature, and safer when climbing or exercising.- Environment-friendly material, strong and wear-resistant, recyclable, and long service life. Packing list: 1 x pair of insoles1 x USB cable1 x remote controller