ITEM NAME:2 x Dog Barking and Training Whistle Ultrasonic supersonic stop bark ke BSL XON.2 pcs Silver Tone Puppy Dog Training Obedience Whistle Keychain Adjustable Pitch. Adjustable pitch, simply tighten or loosen the screw to work out your dogs frequency. It should be noted that this whistle is audible to the human ear, essential for gauging its efficiency.
