To anticipate the same, is this is a simple-to-use entry-level device, which in turn but is not intended to negative rating. This TENS unit is already very good, but there are devices that can provide more. But who wants to get to know this method only once, is absolutely right here. My first TENS unit I got time prescribed by orthopedic surgeons and had not had any bad experiences with it. However, it was then adjusted to my needs now and in this model one must grope alone ran. But that's not difficult. The TENS unit is really very small and it may well also take on the go. It is not difficult and barely takes space. Two AAA batteries are attached, just insert, plugs the cable to electrodes and to this then the jumbo electrodes. Finish the device and you're set. The batteries I would recommend to use rechargeable batteries. Depending on the frequency of use you have to change even more times. The jumbo electrodes are really big, given their use is number 50 and then you have to reorder. On the electrodes, a protective screen is mounted, just peel and attach to the application back to it, so that the adhesive effect is maintained for longer. There are three programs, shoulders, waist and soles. The former I find very good, waist is with me not so often be used and sole At first I thought, what for? But if one ever tried, and just after jogging, it is a program that I no longer want to miss. The device itself is easy to use. The assembling is easy, it's all very well explained in the manual. There is also displayed, where you should attach the pads. This is quite helpful for beginners. With the top button to turn on the unit, then the knob comes with the selection (shoulder, waist, bottom) and below you can adjust the intensity up or down. You have to decide for themselves, the strongest level it has in any case in itself. Operation is simple and requires no great technical knowledge. Those who wish to familiarize themselves with TENS devices and a little respect for the more expensive devices has is well advised with this entry-level model. I guess that you will sooner or later surely resort to another model. But this is not only small and handy. It is very easy to use and what is important, it is having an impact and is not just a small toy that lets you stream chasing each other through the body. It relieves pain but stress and leads to a well-being. In any case I can only recommend this model and like to give full marks because I have so far found nothing to complain about there. It is an entry-level model, and very good. Have fun with it and get well soon.