Acoustic frequency: 20-25khz Sound mode: 1: continuous; 2: Intermittent; 3: Frequency hopping. Battery capacity: 300 Ma Voltage: 3.7V Charging input voltage: 5V Charging time: 1.5h Product material: ABS Key material: ABS plastic Power adapter: DC5V / 500mA Package includes: dog driver, charging line and instructions Function: Sound training mode; Ultrasonic expulsion interference mode; There are three different ultrasonic waves that can be switched; High power; When the power is low, there will be an indicator light; Rechargeable, long endurance; Application range: 5m Dog Bark Control and Dog Training - Our ultrasonic anti bark device provides a safe and effective solution for dog training and bark control. The anti bark device can effectively train your dogs to stop unwanted behaviors such as barking, digging, eating unsafe food, fighting, etc. Suitable for All Size Dogs - The average human hearing frequency range is 20HZ~25KHZ, so the sound doesn't affect humans, but can grab dog's attention. Convenient to Use Outdoor - ultrasonic barking dog deterrent just fits nicely in your hand and comes with an adjustable anti-static wrist strap. As we use ultrasonic technology, it works effectively on all sizes of dogs. User's Guidance - The ultrasonic anti-bark device doesn't effective in dogs with hearing problems and we don't recommend using this product on dogs under six months as it may disrupt the dog's development in hearing. Training is required to achieve highly effective and long-lasting use.