Initially I was a little hesitant to buy this because I felt bad at the prospect of shocking my dog. But I had actually tried everything to get him to stop, we have been training him for a year (he was a stray) and he barks at every little noise (not a barker because he is bored).
I tried the collar myself and it is a quick zap (very much like static electricity shocks). The collar emits a beep when it shocks.
My dog cries when it shocks him (but he also cries at just about everything in general). He doesn't appear to be afraid if it, he sits and lets us put it on him no problem. He has figured out that he can whine and growl with it on and it doesn't correct him.
This is fine with us, I would prefer that he is able to make noise, this just keeps him from actually barking which is what can be heard through our apartment walls and bothers our neighbours.
We also verbally correct him when he starts growling or whining, we say "NO" and "be quiet." We have been rewarding him with a small treat after we say be quiet and he is quiet for a few minutes.
This collar is a great training tool for those that use it properly.
I LOVED THAT IT DOESN'T REACT TO SOUND! This collar, if you didn't know, detects the vibration of the dog barking, it doesn't shock when it hears a sound, this is great because I have read terrible reviews of the shock collars that shock your dog when a loud noise occurs.
Such a great product