NPS Pro SONIC BOOM 2023 Upgrade: While only 10% of dogs become immune to our already advanced 25kHZ dog barking control devices we refuse to stop short of 100% effectiveness, so we added an undulating 20 to 30 kHZ 10 second ultrasonic boom. 100% painless. 100% effective. For 300% faster dog training than a dog whistle to stop barking, dog clicker for training, bark box, bark collar, air horn for dogs or in person dog training program.Stops Behavior in Seconds - 50 Feet Range - Skeptical? See It in Action - Dont believe us. Watch the videos in the NPS anti barking device section and see for yourself just how quickly, effectively and painlessly this dog deterrent transforms every annoying, destructive and unsafe behavior in under 3 seconds. The ideal pet corrector for any dog age 6 months to 8 years who barks, chews, bites, chases, jumps up, digs, or eats dangerous objects.Makes Training Stick - 2.7x More Effective than the most expensive, effective dog behavior training on the market with a 3 Tiered Procession that puts you in full control; 4x Chase-Stopping Sounds, 2x Bark Eliminating Sonic Waves, 1x Police Bright Ultra-Deterrent Light & even a flashlight to enjoy those late evening strolls.Rapid 4 Hour Charge = up to 3 Month of Use: More than the fastest, safest dog training method in the world - with 0% pain or damage to pets or people - this is the dog barking deterrent to get if you want to skip the hassle of keeping yet another thing plugged in because it rapidly charges in 1 hour, with a full 60-90 days of charge when connected for four.Love it, 100%, and agree that it's the best dog training device available anywhere in the world or we'll extend a full, fast, friendly refund without question. We're that confident you'll love this advanced ultrasonic dog bark deterrent sleek, compact design; brilliant funcationality, rapid charging capability, and most important - how it helps your dog happily understand how to integrate into your family's life - without any shocking, frustration or pain!