In most of my posts about pain relief gift ideas, I’ve always included the TENS unit as one of the top gift ideas. In fact, I’ve tried to introduce it to anyone I know from my family to my friends and co-workers who are suffering from muscle and joint pain. Unlike other posts where I’ve introduced different practical gift ideas, in this special post, I’ll focus only on the TENS device, including answering fundamental questions such as what it is, how it works, and which ones are rated as the best TENS units by pain sufferers.