I have a friend in Texas who loves these and swears by them, so I give it three stars based on that. HOWEVER. if you have a water-loving dog, these are not for them. It says on the packaging that will diminish their effectiveness. My dogs are in and out of the water at the beach and our pool all the time. Also, my dogs play really rough with each other and had no problem getting them off. For us, they last 2 months max. So, they're a no for us. If you don't have these issues though, I'd say go fSee full review