"I have two dogs, one Jack Russel/Whippet mix, and one Daschund mix. Both dogs bark at everything i.e. the door bell, someone knocking on the door, people passing by, other dogs passing by, people talking outside, etc. Their biggest problem is bicycles. I purchased two of the bark collars because we are currently living in Germany and it is a nosie violation to have barking dogs. My Jack Russel mix is especially bad about once he starts barking he can't stop. The Daschund mix is good at getting my other dog all riled up so he's the one that gets into trouble. The first day I put the collars on my dogs, the barking stopped. I practiced knocking on the door to get them to bark. They both barked once and never did it again. My only concern with this product is that my Daschund has figured out how to "trick" the collar. She grumbles or half barks once and waits for the collar to reset and then does it again. This really isn't even a problem since the continous barking has quit. I can definitely tell when the battery is dead on the collars because the barking starts up again. I would recommend buying an extra battery when you buy this product. This has definitely been a life saver. :)"