Place the PetSafe® Anti-Bark Collar onto your dog. When your dog barks, a harmless Static Correction is emitted. The collar automatically adjusts the level of Static Correction to your dog's temperament; up to 10 levels of correction. The Temperament Learning System contains software that tracks the number of corrections needed to substantially reduce (and in most cases eliminate) the number of nuisance barks. And our exclusive Perfect Bark™ technology ensures that only a combination of sound and vibration from your dog can activate the collar.