CERABED TOURMALINE HEATING MAT is inset with disks of 700 natural tourmaline gemstones. When the tourmaline stone is heated, it emits infrared rays that penetrate the body 14-15cm (5.5 to 6 inches). The rays not only benefit the muscles on the surface of the body but deeper parts of our body. These rays vitalize the biological function of our cells and increase circulation, relieve neuralgia, backache, arthritis pain, eliminate toxins from our blood. It helps to improve microcirculation and metabolism.