USB heater: Can be plugged into any 5V USB port, such as chargers, power banks, USB car chargers, etc. If you are looking for a way to warm your feet in the cold winter, foot warmers are perfect for you. When your feet warm up, your body won't feel cold. Washable: Under-desk electric flannel foot warmer is removable for easy and convenient cleaning. With an invisible zipper, the cushion wrap can be divided into sleeve and inner heating jacket. Soft Material: Artificial flannel material, warm and comfortable, the maximum heating temperature can reach 50 at 60 degrees Celsius. And this heating pad for home office will automatically turn off once the temperature gets too high. Multi-purpose: keep warm and relieve pain, it's a great warming for patients with arthritis, cold soles and menstruating women. Protect your feet from poor circulation, arthritis and cold floors. In addition, this electric foot warmer can effectively relieve muscle, chronic pain, promote blood circulation, relax and warm legs. Widely used: instant heating, suitable for home, office , outdoor camping, etc. Both sides are extra plush flannel, which is very durable and warm. Only the bottom has heating wires (for safety), but the soft thick flannel cover will keep the fire inside the cushion and keep you warm.