The Train Right! Professional Silent Dog Whistle with case features an adjustable tone that carries a long distance. This silent whistle is inaudible to you, but your dog will hear it and respond. It is audible up to 500 feet away. Use this silent whistle to call your dog back to you during outdoor activities. Features: *Quietly communicate outdoors with your dog. *Adjustable tone can be used to train your dog to complete various tasks. *Frequency can carry up to 500 feet away. *Almost completely inaudible to the human ear. *Includes carrying case for covered transport. Applications For calling your dog during outdoor activities.