Massage Action: Percussive Power Source: AC power The G5 ProPower Handheld Massager is beneficial to anyone who competes, works out, or is involved in strenuous work. Before an activity, use it to enhance flexibility, increase range-of-motion, and reduce the risk of muscle spasms, strains or contusions. After exertion, rely on the ProPower to accelerate the healing process, to reduce pain and swelling by flushing out lactic acid buildup in the muscles, and to relieve muscle pain caused by work and stress. It is excellent for the relief of, repair of, and resistance to repetitive motion disorders. (Carpal Tunnel Syndrome, tendonitis, tenosynovitis, etc.). This portable and light weight ProPower is a hand-held device with a soft rubber grip and variable speed control of 20 to 50 cycles per sec.