Foundation Premium TENS Unit N602 Cost new $100. Includes new replacement pads. ($15) A transcutaneous electrical nerve stimulation (TENS) unit is a battery-operated device that some people use to treat pain. TENS units work by delivering small electrical impulses through electrodes that have adhesive pads to attach them to a person's skin. N602 is a TENS unit that incorporates a wide variety of output combinations. It has a timer of 15, 30, 60 minutes (or 15, 30, Continue) and three modes available: B(Burst), N(Normal) and M(Pulse Rate Modulation). Pulse rate, pulse duration and intensity are adjustable. See how it works here: https://www.painscience.com/articles/transcutaneous-electrical-stimulation.php Find user manual here: http://www.amgmedical.com/site/Manuals/715-420_Ins_EN.pdf Channel: Dual, isolated between channels Pulse Amplitude: 0-80mA peak to peak into 500 ohm load. Pulse Rate: Adjustable, from 2Hz ~ 150 Hz Pulse Width: Adjustable, from 30 μs ~ 260 μs Mode: B, N, M TIMER: Selectable, 15, 30, 60 Minutes(or 15, 30, constant) Wave Form: Asymmetrical Bi-Phasic Square Pulse Voltage: 0-40 V peak into 500 ohm load Size: 95(H)× 65(W) × 23.5(T) mm