NATURAL DEEP HEAT THERAPY : TheraCool large heating pads (22"x13") contain all natural clay beads that hold heat longer to relieve neck and shoulder pain , back pain , stress , stiff muscles , tense spasms and cramps. EASY TO USE : With a quick 2 minutes in the microwave the TheraCool clay bead hot compress provides you with a soothing and long lasting moist heat that deeply penetrates the muscles OR let the heating pad cool in the freezer for a refreshing chilled experience THERAPUETIC RELIEF : TheraCool heating pads contain soothing, relaxing, and de-stressing aromatherapy scents of lavender and lemongrass. The warming compress is weighted and multi-sectional so the clay beads do not migrate to just one area.