... switching on this product and put it in the quit in winter. If you want warming while sleeping ... , it can be put under bedsheet.4.Warming waist knee, and back ... lumbago, rheumatoid arthritis, neck ache, foot ache, and other aches, numbness, blood cold. Switching on 5 ... if you feel bad in using this product.3.Person with graveness illness, fever, wound, red and swollen ...