Tens Unit Dual Channel 3 Mode w/Timer

System includes device  lead wires  four self-adhesive reusable electrodes  9V battery  hard plastic carrying case and instruction manual * 3 Modes: Standard  Modulate and Burst * Dual Channel *  30 and 60 minutes or continuous timer * Adjustable Pulse Width: 50-250 Microseconds * Pulse Rate: 2-150 Hz * Pulse Amplitude: 0-80 mA each channel * Waveform: Asymmetrical biphasic square pulse * One year warranty * FDA approved * Prescription required *