Is the effect of Yi Tian stuttering corrector produced by Zhejiang Tiantai Medical Instrument Factory good?

I also found this on the internet. After some tangled consideration, I finally made up my mind to use this product to correct it. I felt it after a few days, so

I'm serious.

I used it. I read the instructions written by their company carefully. Personally, after using it, I feel that it is very effective to take a deep breath before speaking, and then use the instrument. You can have a try.