The PetSafe PBC00-11216 Outdoor Bark Control System deters your or your neighbor's dog from excessive barking. When the Outdoor Bark Control is within range of a barking dog, an internal microphone picks up the sound and the unit is automatically activated. The PetSafe® Outdoor Bark Control emits an ultrasonic sound that can be heard by dogs but is silent to humans. Startled by the high-pitched sound that is safe and effective, the dog should stop barking, as it will associate its bark with this unpleasant noise. When the dog stops barking the ultrasonic sound also stops. The PetSafe Outdoor Bark Control has 3 sensitivity levels that control what barking level activates the unit. It is effective up to 50 feet.

Note: If the dog is deaf or hearing impaired, he may not react to the Outdoor Bark Control.