First of all, I had put it in the basket to see it again and I had forgotten about it, so I accidentally bought it on my next purchase! Okay, I don't earn IQ points for that!
When it arrived, I decided to try it instead of returning it. The packaging has 2 pieces, so I kept one and gave the other to someone else. Our opinion about the product is the same.

It doesn't sit comfortably on the shoulders and constantly needs adjustment to avoid falling off. It is not convenient for sleeping and restricts side positions to stay relatively stable. Essentially, if someone doesn't feel comfortable sleeping like a corpse, it's better not to pay for it. To do the job it promises, the user needs to wear it for a few hours, but this is not feasible for the reasons mentioned above. Lastly, the size is very uncomfortable.

Overall, your money will be better spent on almost anything else other than this.