If your dog (or your neighbors) is driving you bonkers with his barking, help is here! Our ultrasonic outdoor bark control unit looks like an ordinary birdhouse that can hang in a tree, on a fence post, or anywhere outside. It can detect barking up to 50 feet away and has 3 range settings. Whenever the dog barks, he will hear the high-pitched sound (inaudible to humans) that will teach him to stop his annoying habit. It features 4 levels of operation, runs on a 9V battery with a low battery indicator light, and it is durable and weatherproof.