We got it for back pain and it did absolutely nothing. I hadn't noticed that it doesn't produce heat when I bought it, but if it actually worked, I wouldn't mind. Of course, there are patches where just one is enough to do the job. In fact, that's how patches work. If you need to use four for it to work, it loses all the practicality that a patch is supposed to offer.

extremely effective patch. it has saved me from back pain that causes intense muscle spasms. it offers me complete pain relief. just to emphasize for those who say it has no effect... you can't just put a small patch on the area and expect miracles. at least for my back, I use 2 to 4 pieces. this way it covers the whole area and has a complete effect...

I was influenced by the positive comments and bought several pieces. And the result was...zero! Literally nothing.

I didn't want to be unfair and tried several times before reaching a final judgment, both for muscle pains and for my back or wrists, but every time the same...nothing.

I gave a few to my colleagues and relatives who were facing various muscle problems, over 4 users that is, to tell me exactly the same. That it offered them nothing.

I would not recommend it.

Note: No, it does not warm the area.