UPGRADED LCD SCREEN: visualize the battery level of the anti bark device, and it will make BB warning sound when the battery level is low. The barker has a lock screen function, short press the key to lock the screen after turning on the barker. In the lock screen state of the barker can work normally, just the screen does not light up, more battery saving, tested, the barker can work up to 10000+ times if using 9V 6LR61 alkaline batteries (not included). 4 SENSITIVITY MODES: Auto, high, medium, low mode, high sensitivity mode represents the dog barking control device can release ultrasonic waves when sensing lower barking sound; auto mode the anti bark device can automatically adjust the sensitivity. The newly upgraded automatic mode makes the anti barking device more intelligent and more effective in managing dog behavior. 0-9 FREQUENCIES: in the three standard modes the frequency is fixed and can be selected by human; in the automatic mode, the dog bark deterrent device can automatically select the appropriate frequency each time when receiving the barking signal, the frequency is not fixed. Different dogs react to ultrasonic waves at different frequencies, so for best results, we recommend testing your dog's reaction at different frequencies and then choosing the most suitable one.