New 4-Core Ultrasonic Anti-Bark Device Smart Dog Bark Control Humane Pet Trainer

With 4 ultrasound heads. to form a conditioned reflex. The principle of a bark stop device is that when the dog barks, ultrasound will work. 【3 Adjustable Ultrasonic Levels 】Features three adjustable ultrasonic levels (10-16KHz for small dogs;. ).

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