So I was able to get this discounted and definitely needed one because of my back hurting and just normal wear and tear on an old body.
This Santamedical PM-510 Tens Unit is no bigger than a credit card and a little thicker than an iPhone 5.it is rechargeable by provided USB cable since comes with 4 pads amass 2 cables with 2 leads on each cable for the pads. It is easy to use and easy to learn. The power from this little machine is amazing and powerful. It has various functions and timers and controls are not touch screen but you can click them easily.
The trick with these units is to wash your area first and apply right after lightly drying your skin. Keep the pads clean but don’t wipe them. When they do not stick anywhere then just toss them out. This is a great unit for the price and quality. Battery usage varies on how much you use the unit but I’ve recharged mine one time in 4 days with using it 2 times a day for 20 minutes.
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