Material The training whistle is made of high-quality stainless steel, which is sturdy and durable. The sound of the whistle is transmitted by ultrasonic waves and will not affect your dog's hearing. It is very suitable for dog training. Adjustable Frequency Our ultrasonic dog whistle can reach a finer frequency range that humans can hardly hear, but it is very good for dogs and can train dogs to perform different actions. Anti-lost Design Our dog whistle contains a high-quality lanyard. It can be hung around the neck and will not be easily lost due to its small size. Easy Training Our dog whistle can reliably stop your dog from barking and help your pet learn commands and techniques. It is suitable for sports, hunting, herding, guide dogs, and rescue dogs. Wide Range of ApplicationsThis high-quality small whistle is suitable for training small dogs, medium dogs, and large dogs. You can always find the best frequency for your dog. Length: 8 cm Package includes: 2 Dog Whistlegetveryrich