Review on GoodBoy Mini No Shock Remote Collar For Dogs - Beep & Vibration Modes, Waterproof, 1000 Feet Range - Pet Behaviour Training For Small To Medium Dogs (Blue) by Jason Hill

I really did not think this collar was going to work for my mini-schnauz. She was dart crazy once she could find an opening. This collar worked immediately on having her stop and turn back. I thought for sure I would need to shock the heck out of her but found out the 'sound' works just fine. Now we have a second mini-schnauz and this one is even more challenging. She just doesn't want to listen. I've had to shock her a few times, but mostly she'll respond to vibration. In fact, I've noticed that she now is responding to the 'sound' so it seems like it is working in that regard. I don't even put the collar on our first dog anymore. She behaves. I'm buying a second one because the prongs that hold the transmitter have fallen off so my advice would be to make sure you check those for tightness, which I had not been doing.