This is something I personally would not put on any dog I owned.
Dog ownership requires patience and training. You owe it to yourself
and your pet to keep him safe. Yes, it takes hours, days and sometime
months to get him trained they way you want but it's worth it.
A dog that does not like a leash is a dog that is not worked with.
Any dog can learn to be leash trained and trained for almost anything.
It's the time, patience and constant repetition that people don't want
to do and in place of this look for alternative ways to train. This is not
training, it's just an easy fix and the poor dog get's to get the shock!
If your not willing to put in the time to train the way a dog should
be trained then a dog is not for you.(meaning anyone)