Transcutaneous electrical nerve stimulation. The art of self-zappin'.
Electricity can be a friend, or a foe. It can blow up trees when it's in the form of lightning. But it can also help get rid of some nerve-related pain issues when it's in the form of TENS.
How does it work? To be honest, we don't really know. We assume it's some sort of interaction with a human's natural body electricity. Maybe it works using feedback, or maybe it just scares away the bad electricity. We really have no idea! All we know is that it helps a little. And if you're in pain, maybe that's what you want?
But please, use this TENS Stimulator properly. After all, safe as it may be, it's still electric. It deserves some respect.