Description: The insoles can be trimmed and tailored to fit any size with it soft texture, which can provide you with relaxing warmth and comfort by self heating. You can place it inside your shoes or slippers and enjoy warm, which can keep your core body temperature in balance with its constant temperature, and it is anti-slip and no odor while using. Made of sponge material, this product is wear-resistant and long lasting. There are 6 sizes that you can choose from: 35, 37, 39, 41, 43, 45. It is perfect for outdoor activities skiing, hiking, fishing, cycling, hunting to prevent your feet from cold. Item Name: Self Heated Insoles Material: Sponge Features: Self-Heated, No Odor, Comfortable Size Details: Size: 35, Length: 23.5cm/9.25" (Approx.) Size: 37, Length: 24.5cm/9.65" (Approx.) Size: 39, Length: 25.5cm/10.04" (Approx.) Size: 41, Length: 26.5cm/10.43" (Approx.) Size: 43, Length: 27.5cm/10.83" (Approx.) Size: 45, Length: 28.5cm/11.22" (Approx.) Notes: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Package Includes: 1 Pair of Self Heated Insoles