Rite aid tens/ems heat device is used for temporary of pain associated with sore and aching muscles in the shoulder, waist, back, upper and lower extremeties Transcutaneous Electrical Nervce Stimulation (TENs). Muscle Stimulation for training and regeneration (EMS). 2 Heat Settings. TENS/EMS or heat function can be used in parallel or separately. Rechargeable battery with included charging cable.