Preferred plus Heating pad moist, dry therapy king size. Heat therapy relaxes muscles and relieves joint pain and soreness. By increasing blood flow to the injury area, heat therapy can help accelerate healing. Finally, heat can effectively warm and loosen stiff muscles before exercise. Moist/Dry heating pad with smartheat technology. MartHeat electronic controls provide four precise temperature settings for a more comfortable and effective therapeutic treatment. Ergonomically designed controls fit comfortably in any size hand for easy temperature selection. Automatic shutoff after 30 minutes allows optimal therapeutic heat treatment.