The boot-shaped design can warm the whole pair of feet, up to the calf. This can lock in heat and increase blood circulation, making the feet warm quickly. And the part of the boots has been reinforced. It will not cause it to slowly collapse or slip off, preventing cold air from entering the foot. Unlike traditional heating pads, we boldly use the design of 6 levels of temperature. From 104℉ (40°C) to 140℉ (60°C), you can freely choose according to the environment, temperature and your personal preferences. Plug in the power supply, it only takes 30s to heat up quickly and warm your feet. This winter, you need an electric heating boot to warm your lovely feet.