Description Good Material: The main body of the dog whistle is made of high quality stainless steel, and the surface is coated with an antioxidant protective layer, which is durable, fine workmanship, rust-proof and fade-proof. And it wont hurt your dogs hearing during training sessions. Adjustable Multi-Frequency: Dog whistles wont hurt your dogs hearing, the frequency of ultrasonic whistles is adjustable. At first, you can loosen the sound wave adjustment screw, then while blowing into the air inlet, adjust the adjustment lever to the appropriate volume, and finally tighten the sound wave adjustment screw. You can train your dog to listen to different commands this way. Please note that your dog needs to be trained several times to understand your instructions. Safe Design: This professional dog whistle emits ultrasonic waves which are not easy to detect by human ears, but dogs can hear very clearly, so you dont have to worry about annoying high-pitched noises. This dog reminder whistle will help you easily and effectively control your dogs barking. Convenient Practical: The body of the whistle is made of high quality stainless steel covered with a protective cover to prevent dirt, damage and accidental loss. It is purposely small and lightweight to make it extremely easy to wear around the neck with our matching black lanyard. You can also put it on a keychain or pocket. Concentrate on training, it is convenient to free your hands to interact with the dog during training and make this lightweight whistle a part of you. Wide application: the pet whistle is a good tool to train your dog. to sit, come, stop barking and stay according to your instructions, suitable for Poodle, Border Collie, German Shepherd, Bulldog, Rottweiler, Dachshund, Huskie and other breeds. You can also use it for other household purposes, toys or tools.