From the brand Product description 【Safe and effective anti barking】The upgraded dual-frequency ultrasonic combines fixed and variable frequencies, which allows it to be used on more dog breeds and can stop barking more effectively. Dog bark control device can also help you train your dog and correct bad behaviors such as endless barking, digging, chewing furniture, eating dangerous foods and fighting. 【Easy to Use】Just press the button and when you hear the beep, it indicates that the ultrasonic bark control device is sending ultrasonic waves to your dog to warn him to stop barking. Continuous training can achieve effective and long-lasting results. 【Portable Design】The dog bark control device is compact and portable. Easy to carry when you walk your dog, walking or running. The effective range is 16.4ft, perfect for training your dog at home or outdoors. It can also prevent other dogs from approaching you while jogging, walking or running. 【Ultrasonic specially designed for dogs】The