It's every dog owner's nightmare: your dog's running towards a busy road. You want to call him back, but anxiety affects your voice and he doesn't react to your command. It's a nasty thought, but pet owners find themselves in this and similar situations all the time. This adjustable high-frequency whistle offers a way around the problem. The tone of the whistle always stays the same, however stressed you are, and once you've trained your dog to recognize it he'll respond, whatever the situation. Size: 8cm