For indoor and outdoor use universal HEATED SHOE INSERTS USB 35-46 Heated insoles These heated inserts use new heating technology, made of comfortable flexible EVA material, with carbon fiber heating wire, the preheating system heats up slowly, distributing heat evenly. It is perfect for all outdoor activities. Safe and reliable energy-efficient environmental protection, low voltage, safety and energy saving. The heating time depends on the selected battery. The electric carbon fiber heating cable heats the liner, ensuring even heating, high heat transfer efficiency, high heating speed, softness and comfort. Very suitable for various outdoor activities. Adjustable size shoe sizes are in the range of 35-44 and can be adjusted to suit your needs. The size range is marked on the insert, and the lines are marked on the insert for easy cutting. Suitable for both men and women. Heating via USB interface Heating is convenient thanks to the USB interface. The USB port, one end of the USB power cord is connected to the USB port of the computer, and the other end to the insert. Easy to use, simply 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 the cold winter, but also promotes blood circulation and has great benefits for the body. Washable and reusable heated inserts can be cleaned. They should be dried before use (do not machine wash). They can be cleaned with water for recycling purposes, but keep the interface away from water when connecting USB power. Heated insoles adjust the right size to fit your foot size Wide range of applications These comfortable insoles are suitable for all kinds of shoes, such as sports shoes, shoes, leather shoes, cotton shoes, etc. They can be worn during indoor and outdoor activities, homework, fishing, skiing, hiking, working, etc. Wide application warms the insole, which can solve the problem of feet in cold weather and keeps your feet warm throughout the winter without sweating. It has a wide range of applications, including many winter activities such as hunting, skiing, motorcycle riding, mountain climbing or hiking. We strongly believe that a heated liner must be the perfect choice for you! Excellent gift: The heating is even and fast, ensures that your feet are protected from the cold, and also promotes blood circulation, making it the ultimate Christmas gift and a great gift choice. Specification: Product Type: Heated USB Inserts Material: Elastic EVA fiber. Color: zarny. Temperature: about 40 - 50 C. Voltage: 5 V / 0.7 A. Size: 35-45 Length of usb；150cm cable List of packages: 1 x pair of heating pads. 1 x USB cable.