Might be defective
I'm so glad I used this on my practice hand and not a real person. After using it for more than 5 minutes on the lowest setting it started to speed up and get really hot. I had to hurry and turn it off because I thought it would explode or something. If it was on a person it would have really messed up their hand. Beware of it speeding up out of nowhere on the lowest setting.
Rating: 1 stars