Note: It needs to be plugged into a charging treasure for normal use. This heated insole is made of soft and comfortable EVA stretch material, with good cushioning and lightweight portability. The heater has a USB interface used for heating via the USB cable, with a large heating surface and even heat distribution. The temperature can reach up to 50 DegreeC/122 DegreeF. This USB insole material has a waterproof effect, is washable and reusable. You can wash it with a brush, but it is not suitable for machine washing. It should be noted that it needs to be dried after washing and must be completely dried before use. DIY Adjustable Insoles Size: Electric insoles can be cut to your required size, adjustable to your shoe size. The shoe size range is marked on the insoles for your DIY convenience. You don't have to worry about the size as there are lines marked out on the insoles, making it easy to trim. Wide Range of Uses: The heated shoe insole is suitable for skiing, outdoor sports, camping, chores, hunting, hiking, fishing, etc.