4 Ultrasonic Transmitters: 2024 Upgrade speakers, our new sonic bark deterrent is safer and more effective in transmitting ultrasonic waves to your dog, which quickly stops your dogs from barking. Our bark box will work all day to create a quiet and safe environment for you. 3 Operating Modes: Compared with traditional ultrasonic bark control devices, our dog barking control devices not only have 2 ultrasonic modes(20-25KHz), but also designed a sound mode for sensitive puppies. 2 Ultrasonic mode is silent mode, which is inaudible to human ears and will not cause trouble to your life. IP45 Waterproof&Rechargeable: The charging port of the stop barking dog devices is equipped with a lid, you can also control the dog well on rainy days. It can be hung on the tree, fence, wall, anywhere in the house. Our anti bark device supports charging via USB cable. 5 hours full charge can continuously work for 30 days, standby for 60 days. Range up to 33 FT: The automatic dog barking deterrent can detect the dog barks up to 33 feet range, and then emit ultrasonic to stop your dog or neighbor's dog barking, which is completely free your hands.The dog training device is effective for 6 months to 8 years of dogs between sizes (5-80 lbs). It's best to train your dog for 2 weeks. 100% Safe & After-Sales: The dog barking control devices uses harmless ultrasonic technology, which will not cause any harm to humans or dogs.