Blue Color Quantity: 3 pieces Best Training Whistle: This professional ultrasonic whistle is an excellent training aid for any age and any dog. They will ensure that you are fully focused during training and you will hear the sounds from a distance. Ask your dog to stop barking according to your instructions, sit, come, lie down and recall, potty training. Safety Design: It is safe for your dog. After many tests, we can guarantee that the sound of this whistle will not affect the dog's hearing. Avoid using it without discomfort or irritability. Remote Control & Remote Control: Train your dog with an ultrasonic whistle and clicker so you don't need to shout loudly. Even if your dog can't see you, they'll still receive clear signals and commands. Communication between you and your dog becomes clearer and easier. Widely Used: Regardless of the Variety. We ensure that our ultrasonic whistle can be used effectively for all dog breeds, regardless of size. You can also use it for other household purposes, toys, or tools.Good Quality Product