The TENS 3000 analog unit uses a microprocessor, which gives exact dial performance. Benefits includes maximum full strength power of 80 mA. The TENS 3000 is as accurate as a digital unit, yet easy to operate. The safety amplitude cap protects the amplitude knobs from accidental bumps or knob movements. System includes device, lead wires, four self-adhesive reusable electrodes, 9V battery, hard plastic carrying case and instruction manual. Power Source: 9-volt battery. Modes: Standard, Modulate and Burst. Channels: Dual. Timer: 30 and 60 minutes or continuous. Pulse Width: 50-250 Microseconds, Adjustable. Pulse Rate: 2-150 Hz. Pulse Amplitude: 0-80 mA each channel. Waveform: Asymmetrical biphasic square pulse. One year warranty.