This product doesn't work at all. Its suppose to send out an electronic sound to stop barking but really did nothing. Its also doesn't look comfy around a dogs neck. It is not a shock collar just a collar that is suppose to make a beep sound.
We tried these for 3 weeks with our 2 dogs. They bark constantly if they are left outside or if someone knocks on the door. We didn't see any change in their behavior and it was very easy for them to take the collars off.