1.NOTICE: It will take several training sessions to get your dog to listen to your commands. Please be patient and work with your dog frequently. Please see the pictures below on how to adjust and use the whistle. 2. DUAL DOG WHISTLES WITH ADJUSTABLE FREQUENCIES: Dogs may have different reactions to voices of various frequencies. Train your dog with precision using our dog whistles, each equipped with adjustable frequencies for optimal dog training. Our dog training whistle body is crafted with stainless steel with a nut and screw mechanism that enables you to adjust the frequency by turning it. 3. Control Dog Barking: If your dog or your neighbor's dog keeps barking, gently blow the dog whistle, the ultrasonic frequency emitted by our silent dog whistle can easily attract your dog's attention and effectively stop the barking. This ultrasonic dog whistle is suitable for all dogs. 4. STYLISH LANYARD ATTACHMENT FOR CONVENIENCE AND FLAIR: Each dog whistle comes with a stylish lanyard for easy attachment. This serves as a convenient way to carry the dog whistles and adds a touch of flair to your dog's appearance during training. You can hang the dog whistle on your neck, to prevent it from being lost. The wrist strap is elastic and retractable. 5. BONUS ERGONOMIC DOG CLICKER: Enhance your training sessions with the included dog training clicker. Our Dog Clicker is a versatile tool that reinforces positive behavior and is a great addition to your training toolkit.. You blow different sounds from our clicker dog trainer so that the dog can read your meaning according to the sound and make some actions.