As I searching online for some tips on training a dog, I saw this dog training collars which they said that is one of the most useful tools used for training. It is primarily used to correct bad habits such as barking, digging, and chewing, a Training Collar can transform a misbehave dog into a well obedient dog. What do you think? Are these actually effective or is it just some sort of industry push to sell products? Any suggestion will be helpful to me.