TENS Unit and EMS Muscle Stimulator ComboOTC TENS Device with Accessories,Black

It's a super unit, works great. For me it did require reading the manual due to having a couple more options than I was familiar with. Very impressive company when I posted a question they responded immediately with what I needed. For the low price of the unit the quality and support has been a nice surprise.

easy to use and quick delivery

I have no background in this area, just some initial observations that might help:When the knob is turned on (like a volume knob), the device is immediately sending electricity to the pads. For some reason, the overly warning-filled instructions failed to make that point clear, except to say that the pads should be on, then turn on the machine. But in order to figure out the settings, you have to turn the knob on. So basically, in my opinion it would be better to not connect the wires, turn on the device, figure out and explore the settings, then turn it off, then connect and put the pads on, then turn it on to the lowest setting and very very slowly turn it up. Very slowly because its output is uneven. For me it felt like nothing until I got to 4, at which point it was a strong zapping and my leg locked up and I dropped the EF device I was carrying. Here's the setting for EMS I tried as a first attempt that got a full muscle contraction (though on second thought I'd prefer to start out with ramp at 1s and on at 2s, I just didn't know that on has to be at least 2x whatever ramp is at the time):Delay = 5s200ms, 50hzRamp = 5sContraction / on = 10sRelax / off = 10sAnd for that setting, I put an EMF device next to the pads and measured the volts per meter electrical field that the device produced:1s: 80v/m2s: 76.1v/m3s: 74.7v/m4s: 77.4v/m5s: 90.8v/m6s: 124.4v/m7s: 137.2v/m8s: 120.2v/m9s: 95v/m10s: 84.9v/mSo this means that the "ramp" time is a part of the "on" time. If the ramp time is 5 seconds, then the min on time is 10 seconds, but if the ramp time is reduced to 1 second, then the on time can be as short as 2 seconds.The picture attached shows the graph of the electrical field intensity and each dot represents 1 second in time. I will note that I did this electrical field test because the device's display seemed to rarely match the output of the machine, and the strength of the zapping, seemed very inconsistent. But by running this test I can see that the device's output is very consistent, as well as what is meant by ramp, and that the inconsistency is merely a combination of the display not matching the power output as well as the variation in connectivity / conductivity of the pads, and perhaps my own senses as well. Another thing I didn't see in any of the marketing or descriptions is that the adhesive on the pads is very slimy, which feels strange, but is comforting that the sliminess means the adhesive isn't a "one and done" and that it can last a number of times. My next step will be to find ways to find or make electrodes that do not require replacing, as that is the most universally absurd part of these TENS and EMS devices from both a cost and environmental standpoint. I will not post my results on this progress due to the safety implications of making my own product, but manufacturers should have endeavored to give consumers a long-lasting electrode product as the default option, not one that fills the world with more E-waste by design. However, among all the devices on the market, this one still seems to be the best mix of price and function. Using knobs was a good choice because it can be quickly turned down whereas other models made that part digital, so any mistake would have to be corrected by ripping the wires off in that moment of panic rather than turning the knob down (intuitive).

I Liked the product and I'm using it for both my knees and back

Good product for the price , my physical therapist likes it too. The pads need to be larger but I was able to get some my physical therapist.

Like the item, just found the directions a little confusing.

Have used similar products previously so I'm familiar with the settings and controls. But on this one the intensity controls (which are combined with the channel switches) are defective; it is either off or ON AT FULL INTENSITY. Not pleasant or therapeutic. Returning.

It works great but only at 30 minute intervals. I have to reset it several times during usage.