The control range is 16.4ft. The dog bark deterrent can be used either indoor for stopping unwanted barking and house-training your puppies. The ultrasonic anti barking device can also can be used for dog walking, training them to behave well in public and protect them from eating unsafe food. How Does the ultrasonic anti-barking deterrent device work: Press the ultrasonic anti bark stopper button for unwanted dog barking and the speaker emits an ultrasonic sound, the sound can only be heardby dogs.When pressing the ON-OFF button, you will hear a slight beep sound and a green light will illuminate the dog ultrasonic anti bark device. The products are functioning normally.If the press and hold the button for 6 sec, the ultrasonic anti barking device will shut off.If the dog shows no response, it's because it doesn't understand themeaning of sound wave. After repeated a few times, the dog will learn that its barking will bring