Outdoor Bark Deterrent - Whenever your dog - or your neighbor's dog - barks, he will hear a safe, high-pitched sound (inaudible to most humans) that will cue him to stop his annoying habit. - Are you the owner of a chronic barker - or a neighbor to one? Modeled to look like a birdhouse, the bark controller is battery-operated and has three settings plus a test option. Our ultrasonic outdoor bark control unit looks like any ordinary birdhouse that can hang in a tree, on a fence post or anywhere outside. Features: Range: Up to 50 feet 3 range settings Durable and weatherproof Two-color LED for good/low-battery indication Uses 9v alkaline battery (not included)