Adjustable Sensitivity - This large dog bark collar offers 7 sensitivity levels for all possible barking volume and for different environments, ensure that you can set the right sensitivity level for your particular furbaby. Level #5 is the most sensitive setting and is suitable for dogs from 15 to 150 pounds in size. No False Trigger & Unique Test Mode -The shock bark collar has a strict false barking detection that can intelligently recognize your dog's unique barking and filter out other sounds. When the sensitivity level is adjusted to 0, the receiver enters the test mode, and you can test by blowing or shouting at the sensor microphone on the back of the receiver. Dual Modes & Smart Bark Control-The receiver is designed with a LED indicator display to show the level, and red light for "beep + vibration + shock" mode, green light for "beep + vibration" mode, each mode has 1-5 adjustable intensity levels. Following the nature and behavior of your pet, choose the trigger sensitivity from 1 to 7 by the power button to stop dog barking.