I've been wanting to own a Tens pain relief kit for sometime. Now, I can say that I have one! I've been using my SantaMedical PM-120 Rechargeable Tens Unit for a about a couple of weeks now. I like that there is a LCD display, that the controller is small and lightweight. It's very easy to use and there are 6 auto programs and a manual mode. The default setting is for 20 minutes but you can go up to an hour and continue after that, if you wish. I have a few favorite different modes that I like to mix up for use on my lower back or my arms, whatever is causing aches/pains. You can also increase the strength levels. I usually don't go above 2 levels. That's just what I feel comfortable with.
I always place the electrodes back onto the small plastic pieces when putting everything back into the box so that they can last longer. Overall, the SantaMedical ElectroTherapy Pain Relief tens kit is a great product to use in the privacy of your home and it's something that you could take to work with you as well to relieve muscle pain.