Train your dog to stop barking.
Ultrasonic and audible mode selections.
Audible: creats harsh buzz to stop barking.
High and low modes ( high for big dogs, low for small dogs)
Dogs quickly learn that their barking causes this irritating sound and stop barking to stop the noise.
Ultrasonic: works by sending out an ultrasonic signal that only dogs can hear when activated by the barking.
The ultrasonic sound is 100% harmless.
Adjustable stretch collar to fit different sizes.
Trigger accurately by bark vibration (can not activate by other dogs barking).

Red light working indicator.
ON / OFF buttons.
High / Low volume buttons.
Powered by 2 AG10 cell batteries (included).
For most dogs, it needs 7 to 14 days to take effect; for few dogs, it needs 4 to 6 weeks to take effect; for very few dogs, it needs longer time to take effect