3X Fast, Humane, No BarkingUsing triple ultrasonic emitters, this ultrasonic dog training device stops unwanted behaviors like barking, chewing, or biting quickly and effective. The alternating 25kHz fixed and 2229kHz variable frequencies keep dogs from tuning it out. No pain, no harmful Barks no more made easy. For best results, aim the device directly at your dog within 50ft. Ideal for dogs from 6 months to 8 years without hearing impairments: Not recommended for dogs with known neurological disorders, including epilepsy or seizures 5-in-1 Anti Bark Smarter Training for Every DogDogs arent one-size-fits-alland neither is our solution. With five customizable modes, including ultrasonic sound, beeps, and a strobe light, you can tailor training to your dogs temperament. This bark deterrent device works with 97% of dogs and stays completely safe to human ears. No harsh bark collarsjust humanue behavior correction. Please short training sessions and moni