Bark collars are like the flute for the three-headed dog in Harry Potter. No, it doesn’t let your dog sleep but what it does is control your yappy dog’s barking. Eventually eliminating nuisance barking, bringing peace and harmony in your home and neighbourhood.
A bark collar is commonly known as a shock collar, an electric dog collar or electronic collar, e-collar or zap collar... BUT not all bark collars use electric or static “shock” for correction or stimulation. There are some that use the Citronella spray and Ultrasonic as deterrents. Also, most bark collars will give you an option to set the stimulation into a tone-only or vibration-only mode - perfect for timid dogs.
Now, can these “shock” collars possibly hurt a dog? No, they cannot. Bark collars are designed to distract a dog from nuisance barking and not to punish nor hurt a dog.