Rapid warming, good heat preservation, long service life, easy to install, prevent knee frostbite, cold and numb, stimulate the meridians of the knee joint, in order to increase its metabolism and immunity, promote blood circulation, the body from wind, cold, damp and poison - improve the cells of the blood, relieve pressure, improve sleep quality, accelerate the metabolism, activate cells, beautify skin, reduce weight, great gift for your friends and family, especially in this cold winter