The only TENS in the world with heat! Relieve those sore, aching muscles with FlexHeat. By combining TENS and EMS, FlexHeat is an effective pain management source. With multiple settings and 3 heat modes, FlexHeat will provide relief to those everyday aching muscles and soothe the pain of various medical conditions. Can use TENS only, heat only, or a combination of both. No other unit in the world offers the simultaneous combination of TENS and heat.