Ultrasonic Bark Control Device, Anti Barking Deterrent, Training Tool, Stop Barking, Safe for Dogs, Indoor/Outdoor use, up to 50 Feet Range Upgraded tech stop excessive, noisy dog barking by emitting an ultrasonic sound to silence the dog. More effective than old version deterrents and waterproof. 100% safe -- trusted by Dog trainer & veterinarians. No electric shock, no liquid propellant is used, and most humane and used widely way to keep your own dog or your neighbors dog from barking. For dogs of any size - uses high-frequency sound that works to reduce excessive bark of dogs within hearing range; for dogs 6 months and older up to 50 foot range. Two LED battery status indicator, four adjustable Ultrasonic volume levels?- test, low range, Medium range, and high Range. Easy to use. Tested and trusted.