For indoor and outdoor use universal HEATED HEATING SHOE INSOLES USB 35-46 Heated insoles These heated insoles use new heating technology, made of comfortable flexible EVA material, with carbon fiber heating wire, pre-heating system heats up slowly, distributing heat evenly. It is perfect for all outdoor activities. Safe and reliable Energy-saving environmental protection, low voltage, safety and energy saving. The heating time depends on the selected battery. The carbon fiber electric heating wire heats the insert, ensuring even heating, high heat transfer efficiency, fast heating speed, softness and comfort. Very suitable for various outdoor activities. Adjustable size shoe sizes range from 35-44 and can be adjusted to your needs. The size range is marked on the insert and lines are marked on the insert to make cutting easier. Suitable for both men and women. Heating via USB interface heating is convenient thanks to the USB interface. USB socket, one end of the USB power cord is connected to the computer's USB socket, and the other end is connected to the insert. Easy to use, just put on your shoes and plug in the power to enjoy the warmth. No more cold feet! Promotes blood circulation The heated insole not only protects your feet from damage during cold winters, but also promotes blood circulation and has great benefits for the body. Washable and reusable heated inserts can be cleaned. Please dry them before use (do not machine wash). They can be cleaned with water for recycling purposes, but please keep the interface away from water when connecting the USB power. Heated insoles adjust the appropriate size to the size of the foot Wide range of applications These comfortable insoles are suitable for all kinds of shoes, such as sports shoes, boots, leather shoes, cotton shoes, etc. They can be worn for indoor and outdoor activities, housework, fishing, skiing, hiking, work, etc. Wide application warms the insole which can solve your foot problem in cold days and keeps your feet warm all winter long without sweating. It has a wide range of uses, including many winter activities such as hunting, skiing, motorcycling, mountain climbing or hiking. We strongly believe that a heated insole must be the perfect choice for you! Perfect gift: The heating is even and fast, protects your feet from the cold and promotes blood circulation, making it the best Christmas gift and an excellent gift choice. Specification: Product type: USB heated earbuds Material: Elastic EVA fiber. Color: black. Temperature: approximately 40 - 50 C. Voltage: 5V/0.7A. size: 35-45 USB cable length；150cm Package List: 1 x Pair of Heating Pads. 1 x USB cable.