Ultrasonic Dog Training Barking Stopper Handheld Training Bark Control Device, Dog Bark Deterrent Device Pets ProductsOverview: Anti Barking Device: Ultrasonic Dog Trainer is a great device for Dog Training and Dog Bark Control. Ultrasonic frequency (25 KHZ) has a certain effect on dogs and helps you correct their behavior. Its effective for dogs of all types and sizes of age 6 months to 8 y. o. Convenient & Easy To Use: Small in size the Bark Control Device fits perfectly in the hand. You can carry it in your pocket. Anti barking device starts to work with just