There are plenty of fun toys and training tools available for dogs. The Dog Training Ultrasonic Sound Whistle happens to be a simple tool for obedience training. It helps you teach your dog to follow simple commands such as sit, stay, or come. You can use different whistle patterns for each one. All you need to do is turn the screw to adjust frequencies.
Keep in mind that this is not a completely silent whistle. At the same time, it helps you train your dog and even birds. It is compact and fits in your pocket. Have you found better dog whistles? Please share it here.