Spine Care Jade mat is insert with disks of natural Jade stones. When the Jade stone is heated, it emits infared rays that penetrate the body 14-15cm. The rays not only benefits the muscles on the surface of the body b ut deeper parts of our body. These rays soothe, alleviating backache or other soreness, stiffness or aches. Spine Care Jade stone has an unusual crystal structure and is unique among minerals in showing pyroelectricity, which means that when crystals are heated they produce a postive charge at one end of the crystal and a negative charge at the other. Highest level of Negative Ion – over 700 on Jade and FIR-8-14 um.