Self Heated Thermal Insoles Warm and Breathable for Sports Shoes Comfortable Red EU 41-42 Description: Feature: Self Heated Thermal Insoles for Feet, No Need To Charge Material: made of soft and comfortable material, durable, heating constant temperature insole. Principle: The material embedded in the insole can effectively absorb the energy in the environment and quickly convert it into heat and conduct and penetrate from the surface to inside 54 Celsius degree CONSTANT TEMPERATURE HEATING: physical heating, Warm Memory Foam Arch Support Cushion, can be cut to meet variety of shoes, Winter Use Shoe Pads: Self heating, can be washed and cut, heating constant temperature insole, reusable for Winter Use Size Chart: (optional) EU 37-38 245cm EU 41-42 265cm Package includes: One Pair Self Heating Thermal Insole