[THE QUALITY YOU WANT]: Dog Whistle is made of high-quality stainless steel, with excellent surface treatment, and durable. With a black lanyard, it has an anti-lost design. The protective cover can keep the frequency regulator locked and prevent dirt and damage. [ADJUSTABLE FREQUENCY]: The frequency of the recalled dog whistle can be within the range of 5.4 KHz to 12.8 KHz. It can be adjusted inwardly and outwardly through the adjustable screw at the rear end. Keep trying, and you will find the perfect sound for your dog. A lock nut is required to lock the frequency. The dog whistle emits ultrasound, you may not hear it, but the dog can hear it. [DOG TRAINING]: Dog whistle will not harm your dogs hearing, nor will it cause any problems to your dogs health. You can use the adjustable dog whistle to train your dog, train your dog correctly with multiple commands, and let them follow your instructions. After effective training, your dog can hear the dogs whistle from 25 meters away even if it cannot see you. [EASY TO CARRY]: Small size and light weight. You can hang it on a key chain or pocket. Focusing on training is the perfect tool for training your dog. It is very suitable for sports, hunting, herding, guide dog and rescue dog training. [NOTE]: The effectiveness of our dog whistle depends on the proper training of your dog, so that the dog understands your commands and follows your instructions. Dog training requires patience.