Although electric heating wires used in hot carpet are used in common heating areas, our product uses a "Microfiber Carbon Heating Sheet" which generates heat by the seat itself. Thin and not bulky and safe to use without the risk of cutting electric heat wire. After switching on, it generates heat evenly and quickly without unevenness, and can be washed by hand. Although this product warms only one part of the back area, our product warms the collar at the same time. Warming your neck will greatly increase your body temperature and synergistic with your back for outstanding warmth. While other products have 3 levels of adjustment standard, we can adjust it to 4 levels. Warming your neck will greatly increase your body temperature and synergistic with your back for outstanding warmth. While some products are made with a hard material on the outer surface, we use soft nylon. The lining is made of aluminum coated material that has better heat retention than a brushed liner, giving it an unprecedented thermal effect.