Review on Hweey Dog Whistles: Adjustable Ultrasonic Training Whistles for Effective Recall and Bark Control - Set of 2 (Black, White) by Melissa Sanchez

My friend has a dog that barks a lot. Her neighbor has complained about this, so he's trying to find a way to teach his dog to stop barking. I stumbled across this product thinking it might be a good gift for my friend. He used this pipe for about a week and told me it was very effective. The whistle is well made and works great on his dog which has reduced unwanted barking. In addition, it is noiseless to humans as it produces high-frequency sound that protects human and dog ears. All in all this is a great product!