Low frequency pulse Tens physiotherapy instrument. 4 channels, 15 modes, 20 speeds. •9 self-simulation programs. •Adjustable speed and intensity. •6 selectable massage settings. •Easy to use.. Maximum output: < 5V Pulse frequency: < 100Hz Input: DC4.5V Current: <50 mA Power: ≤ 0.25W Uses 3 AAA batteries (included) ABS, metal alloy.