Features: Uses ultrasonic technology to stop barks, recommended level for indoor use is level 1 if need. Four adjustable ultrasonic volume levels - test, low, medium, and high, with LED battery power level indicator. The device uses low-intensity ultrasonic, is silent to humans and not harmful. Safe for small, medium, large dogs. HOW IT WORKS This device is automatically activated by the sound of barking. When the device is within the range of a barking dog, the microphone will isolate and pick up the barking to emit an ultrasonic sound to silence the dog. HOW TO TEST IT ①Adjust the knob to "TEST" button ②Place the item to a position which is one arm's length away from you ③Whistle to the microphone of the item loudly,if the LED blinks Green,and you can hear beeping noise,then the item work properly Package Includes: 1 X New Outdoor Bark Control 1 X User manual Guarantee：DOPA offers a 100% Satisfaction experience! Any reason our product doesn't meet your standards, just send it back our way for a replacement or a full refund!
Shipping Weight: 6.4 ounces (View shipping rates and policies)ASIN: B011CUFR22