You can use just a bell button, a vibration button, or the shock button and all allow you to select the intensity. I bought two, not knowing one kit could be used with 3 dogs. It worked with my dogs in 2 weeks, then with my most stubborn dog, I just picked up the collar and he would listen to me without having to put it on. I haven't used it ever since. I'm selling the new one not the used one. Please know, I hesitated in buying this but tried it on myself to know how the shock would feel. It has the option to make a bell sound and/or vibrate first as a warning, they are different buttons so you can also just use vibration or sound to train. I tried a spray bottle of water first. I love my dogs but my one dog was just too stubborn and thought he ruled the neighborhood. I knew that if he bit someone he would be put down or be killed by a larger dog so this was my last resort.