The innovative IQ TENS STIMULATOR is the latest in muscle therapy and electric muscle stimulation. This small and compact product uses TENS (Transcutaneous Electrical Nerve Stimulation) and EMS (Electrical Muscle Stimulation) technology to relieve muscle aches and tension. It uses its fully rechargeable lithium battery to send electrical pulses to problem areas. The IQ Massager™ Pro IVs features eight massage modes, 20 levels of strength, and an adjustable timer. Portability at its best, you can use it anywhere: indoors, outdoors and it will fit easily even in your pocket.