Size: One Pack Help retrain unwanted behaviors like jumping up, barking, food stealing and place training with Pet Corrector. Pet Corrector is favorited by pet parents and dog trainers worldwide and has become a must-have for retraining bad habits like excessive barking and jumping up. Pet Corrector works by emitting a harmless hiss sound, that mimics warning sounds found from other animals like snakes, geese, racoons and other animals. This sound interrupts their actions and gives time to help retrain "quiet" "no jump" and "no barking" techniques. We love our dogs so training them humanely is important. Pet Corrector is a positive and respectful way to interrupt bad habits & retrain positive actions for peace of mind around the house and in public. When training to prevent excessive dog barking, or to stop your dogs from barking at strangers, we suggest using Pet Corrector in short bursts and never pointing Pet Corrector at your dog, or aiming Pet Corrector at a place on your body. Pet Corrector is strongly discouraged for use with Puppies and should be used at a safe distance from your dog- never to be pointed directly at your dog or close in proximity to their body.