Control your dog's excessive barking in a humane way that actually teaches him not to bark. The Bark Smart uses an ultrasonic tone triggered by your dog's barking that corrects him instantly and consistently. It will even work on your neighbor's annoying dog! This waterproof and UV-resistant bark deterrent is safe and effective and has a speaker range of 25 feet, ideal for dogs in smaller yards. The Bark Smart runs on the included adapter or on four D batteries (not included). The Bark Smart works by sending out an ultrasonic signal that only dogs can hear when activated by the barking. Dogs quickly learn that their barking causes this irritating sound and stop barking to stop the noise. Choose from two modes: audible and ultrasonic. Both modes signal your dog ultrasonically, but the audible mode also emits a tone that you can hear, so you'll know when it's working. An LED also shows when the Bark Smart is active. You can select the device's microphone sensitivity. Pets Minimize