Instruct: Classify the given Amazon review into its appropriate rating category
Query: Really works, albeit a little larger than a normal shock collar

We got this for my little dog because the wife didn't want her getting shocked like the big dogs. I was hesitant but it works. It would probably work for the big ones too but I haven't tried. It's a little bulky, but it has to be because it has a reservoir to hold a decent amount of citronella. We had one of these previously, and it worked for many years.