Anti Barking & Behavior Training DeviceKaiertcat Anti Barking Device aims to solve excessive, noisy dog barking by emitting a ultrasonic, the dog will stop barking, as it will associate its bark with this unpleasant noise.?Product does not include batteries? 9V battery included4 Adjustable Range Levels The Dog Barking Control Devices with 4 levels of operation including a test mode and 3 levels of sensibility, low range up to 15 feet, medium-range up to 30 feet, high range up to 50 feet.Works for Most Dogs Please use this Dog Barking Deterrent Device for dogs 6 months to 8 years of age that are not violent, aggressive, and have normal hearing. Not every dog learns at the same speed. Please allow up to 2 weeks.Safe to Dogs and Humans Stop barking device with sensitive microphone will pick up dog bark, then the unit will automatically activate. The ultrasonic sound can be heard by dogs but is silent to humans. When the dog stops barking the ultrasonic sound stops too.Durable and Waterproofdog barking control devices use high-quality waterproof material. Whether it is a sunny or rainy day, just turn on the switch and you will not get into the trouble of barking.