1. Unlike conventional bark stoppers, after thousands of tests on various dog breeds, we found that our 4hole antibark device offers barkstopping effects. It is safe for humans, userfriendly, and features a sleek design that doubles as home decor. 2. This antibark device offers 3 adjustable modes with varying ultrasonic intensity frequencies. The higher the setting, the more effective the barkstopping results. For firsttime use, start with a low frequency to let your dog acclimate, then gradually increase to higher settings for results. 3. Easy to use: Before operating this ultrasonic antibark device, please refer to the manual for proper placement. Ensure it is used within a 33 ft range. 4. Effortless operation: Designed based on canine hearing principles, this automatic antibark device emits ultrasonic sounds undetectable to humans. It detects barks and activates automatically, then returns to standby mode for intelligent powersaving operation.